Surgical stapler with circumferential firing

ABSTRACT

A surgical stapler is provided. The stapler employs circumferential channels through which staples are deployed along an arc pathway against an anvil surface. The curved channels allow staples with relatively longer legs to be used in the stapler having a smaller diameter at the jaws. Also, by utilizing a curved path, a much larger staple can be placed in the same diameter device. Specialized curved staples for use with the stapler of the present invention are also provided. To further enable the benefits of the stapler with circumferential channels and method of staple deployment, novel jaw reinforcement structures are provided in the present invention. The jaw reinforcement structures are located towards the center or bladeline of the device instead of around the circumference as in conventional staplers, thereby clearing the outer area near the circumference of the device to provide room for longer staples and staple firing components.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of International Application No.PCT/US2015/035379 entitled “Surgical stapler with circumferentialfiring” filed on Jun. 11, 2015 and hereby incorporated herein byreference in its entirety, which claims priority to and benefit of U.S.Provisional Patent Application Ser. No. 62/010,883 entitled “Surgicalstapler with circumferential firing” filed on Jun. 11, 2014 which ishereby incorporated herein by reference in its entirety.

FIELD OF THE INVENTION

This disclosure relates to surgical instruments, and more particularly,to surgical stapling instruments for applying a plurality of surgicalstaples to body tissue.

BACKGROUND OF THE INVENTION

A typical surgical stapler apparatus comprises a handle at a proximalend and two elongated jaw-like members at the distal end, joinedtogether at a hinge. The jaw-like members articulate to open and closeto capture tissue between the jaw-like members. The user controls thedevice from the handle to open and close the jaw-like members, actuatedeployment of staples and in general manipulate and control the device.One of the jaw members carries a cartridge containing staples arrangedin one or more rows. The other one of the jaw-like members comprises ananvil surface against which the staples are driven to deform the staplelegs. Staples are driven out of the cartridge by a caming surface orslider that moves longitudinally against a plurality of laterallypositioned pushers that push each staple out of the cartridge. Thecaming surface of the slider is angled to compliment the angular surfaceof the pushers. Some staplers include a blade that follows the camingsurface so as to cut the tissue between the two or more rows ofdelivered staples.

Surgical staplers are used in a variety of surgical techniques includinglaparoscopic and/or endoscopic or other minimally invasive surgicalprocedures in which the stapler is inserted through a cannula or tubepositioned within a small incision in a patient's body. In laparoscopicminimally invasive surgery, a trocar is inserted across body tissue of apatient to access a body cavity and to create a channel for theinsertion of a camera, such as a laparoscope. The camera provides a livevideo feed capturing images that are then displayed to the surgeon onone or more video monitors. Additional trocars are inserted to createadditional pathways through which surgical instruments, includingsurgical staplers, can be inserted for performing procedures observed onthe video monitor. The targeted tissue location such as the abdomen istypically enlarged by delivering carbon dioxide gas to insufflate thebody cavity and create a working space large enough to accommodate thescope and instruments used by the surgeon. The insufflation pressure inthe tissue cavity is maintained by using specialized trocars havingseals that prevent the insufflation gas from escaping and collapsing thesurgical working space. Laparoscopic surgery offers a number ofadvantages when compared with an open procedure. These advantagesinclude reduced pain and blood loss and shorter recovery times.

As laparoscopic surgery evolves to become even more minimally invasivewith incisions and trocar/cannula diameters becoming smaller andsmaller, surgical staplers for use in laparoscopic, minimally invasiveprocedures must be designed to fit within the small lumen of a cannula.Generally, a surgical stapler is inserted into a cannula with thejaw-like members in a closed orientation until the device jaws areinside the patient where the jaw-like members are opened to grasp andstaple tissue. The handle of the stapler resides outside of the patientin control of the surgeon user. A portion of the shaft of the staplerbetween the jaw-like members and the handle is long enough to extendfrom outside the patient to inside the patient. During the staplingprocedure, the elongate shaft of the stapler resides inside the cannulainto which it was inserted.

The distal jaw-like members include many components such as an anvil forforming staples, a staple cartridge with a plurality of staples, acaming surface, a slider, pushers, a blade and other components whichmust all be small enough to fit through a small diameter cannula andmade to function reliably and repeatedly from outside the patient. Asshown in FIG. 1A, when closed, the distal jaw-like members of thesurgical stapler 2 a have a substantially circular cross-section whereinapproximately one half of the cross-section comprises the lower jaw 3 athat houses the staples 7 a. Approximately a little less than the otherhalf of the cross-section comprises the upper jaw 4 a that houses theanvil. The circular cross-section of the distal jaw includes a gap 5 abetween the upper and lower jaws for receiving tissue to be stapled. InFIG. 1A, a vertical line 6 a divides the cross-section in half andrepresents a blade line or an I-beam that carries a blade to cut tissuebetween one or more rows of staples 7 a. The I-beam slideslongitudinally along the length of the distal end and also functions topush the staples 7 a out of the lower jaw 3 a, across the gap 5 a andagainst the anvil of the upper jaw 4 a. A plurality of vertical lines 7a in FIG. 1A represent three rows of vertically arranged staples 7 aresiding in the lower jaw 3 a on either side of the blade line 6 a. Theconventional stapler design involves ejecting the staplesperpendicularly against the anvil surface.

While conventional laparoscopic staplers are approximately 12millimeters in diameter, it is desirable to reduce the stapler diameterto fit inside a cannula having a diameter as small as approximately 5-10mm to provide the patient with a smaller incision, reduced recovery timeand reduced scarring. FIG. 1B illustrates a reduced-diameter staplerwith the same conventional design as shown in FIG. 1A. As can be seen inFIG. 1B, the smaller stapler 2 b has a smaller diameter with less spacefor a lower jaw 3 b and upper jaw 4 b. The tissue gap 5 b isapproximately the same as the tissue gap 5 b of the larger stapler 2 afor stapling tissue having approximately the same thickness. As a resultof the reduced diameter and conventional design that ejects staplesperpendicularly against the anvil surface, the smaller stapler 2 baccommodates staples 7 b in the lower jaw 3 b that have shorter staplelegs as shown in FIG. 1B. The length SB of the staple legs in thesmaller variation of FIG. 1B is significantly shorter than the length SAof the staple legs in the larger variation of FIG. 1A. This is aninherent limitation of staple leg length in smaller diameter staplersemploying the same conventional design. Hence, it is desirable to have asmaller diameter stapler that is capable of being inserted into smallercannulas while at the same time still retaining the same ability to firelarger staples.

FIG. 2A illustrates tissue 8 a that has been cut along a blade line 6 aand stapled with the conventional stapler 2 a of FIG. 1A. FIG. 2A showsthree rows of staples 7 a delivered into tissue 8 a adjacent to a bladeline 6 a. The other three rows of staples 7 a on the opposite side ofthe blade line 6 a are delivered into a tissue segment that is not shownin FIG. 2A. The distance CA is the length of tissue 8 a that has beenstapled. FIG. 2B illustrates tissue 8 b that has been cut along a bladeline 6 b and stapled with the conventional stapler 2 b of FIG. 1B havinga smaller diameter relative to the stapler of FIG. 1A. FIG. 2B alsoshows three rows of staples 7 b delivered into tissue 8 b adjacent tothe blade line 6 b. The distance CB is the length of tissue 8 b that hasbeen stapled. When compared with the length CA of FIG. 2A, the smallerdiameter stapler 2 b produces a shorter length CB. The length CB isnaturally shorter as staples 7 b are more closely placed in the reducedlower jaw 3 b area.

Also, the cuff length, which is the distance between the blade line orcut edge and the closest staple row to the cut edge or blade line, maybe shorter as longer staples are placed closer to the diameter as shownin FIG. 2B when compared to FIG. 2A. In order to fit multiple rows ofstaples 7 b in a smaller diameter version stapler 2 b, the stapler 2 bis configured to deliver a row of staples 7 b as close as possible tothe blade line 6 b as shown in FIG. 2B. The proximity of this line ofdelivered staples 7 b is much closer to the blade line 6 b than the sameline of staples 7 a in the larger version stapler 2 a. Proximity ofstaples to the blade line 6 b may increase the chances of a misfiredstaple crossing the blade line. Also, proximity of the staples to theblade line results in the first line of staples 7 b being very close tothe edge of the tissue 8 b which may reduce tissue holding. Hence, it isdesirable to provide a smaller stapler that reduces the risk of staplejamming and that provides more tissue between the staple line and theedge of tissue.

In order to accomplish the above-mentioned objectives, a smallerdiameter stapler utilizing a conventional design may require that thedesign includes shorter staples or other design compromises. Hence, itis desirable to have a smaller stapler without sacrificing theabove-mentioned objectives while at the same time retaining the samefunctionality and efficacy in a design with smaller diameter.

Also, many other factors enter the equation for an improved stapler.These factors include but are not limited to reducing the force requiredto deliver staples. Reducing the actuation force improves the accuracyfor the surgeon requiring finesse in a surgical procedure and alsoreduces surgeon fatigue. Typically, when staples are firedperpendicularly against an anvil surface, the staple legs are forced tobuckle. Another factor that creates a better stapler is the strength ofthe deformed staple. For instance, the deformed staple must have a shapethat includes a space for receiving tissue without unduly compressing orsevering the tissue in the location of the staple. Also, the deformedshape of the staple must be strong enough to withstand forces that wouldtend to pull the staple open. Overall, it is an object of the presentinvention to provide an improved stapler that retains the functionalityand efficacy in a reduced-diameter stapler and resulting staple linetaking into consideration the above-mentioned as well as other designfactors. Conversely, it is an object of the present invention to providea stapler having the same diameter as a conventional surgical staplerthat can fire longer staples with circumferential firing than previouslypossible without circumferential firing.

SUMMARY OF THE INVENTION

A surgical stapler is provided. The stapler employs circumferentialchannels through which staples are deployed along an arc pathway againstan anvil surface. The curved channels allow staples with relativelylonger legs to be used in the stapler of the present invention having asmaller diameter at the jaws. Also, by utilizing a curved path, a muchlarger staple can be placed in the same diameter device. In certainembodiments, a staple up to three times larger can be employed in astapler of the present invention. Specialized curved staples for usewith the stapler of the present invention are also provided. To furtherenable the benefits of the stapler with circumferential staple channelsand method of staple deployment, novel jaw reinforcement structures arealso provided in the present invention. The stapler jaw reinforcementstructures are located towards the center or bladeline of the deviceinstead of around the circumference as in conventional staplers, therebyclearing the outer area near the circumference of the device to provideroom for longer staples and staple firing components.

According to another aspect of the invention, a surgical stapler isprovided. The surgical stapler includes a handle assembly connected to astapler cartridge assembly. The stapler cartridge assembly has an endeffector at the distal end. The end effector includes an upper jawconnected to a lower jaw such that the upper jaw is movable via thehandle assembly relative to the lower jaw between an open configurationand a closed configuration. The lower jaw has an upper surface and theupper jaw has an anvil surface. In the closed configuration, a gap isdefined between the upper surface and anvil surface for receiving tissueto be stapled. The lower jaw further includes a plurality of staplechannels arranged longitudinally along the length of the lower jaw andconfigured to receive staples. Each staple channel has an opening at theupper surface. A center point is defined by a cross-section takenperpendicular to the longitudinal axis of the end effector with the jawsin a closed configuration wherein one or more staple channels are curvedabout the center point. In another variation, the staple channels areconcentric about the center point. In another variation, one or morestaple channels are elliptical about the center point. In anothervariation, the stapler further includes a plurality of staples disposedinside the staple channels and each staple has curved legs that conformto the curvature of the staple channels in which they reside. In anothervariation, the stapler further includes a plurality of pushers disposedinside the staple channels that are configured to contact and ejectstaples and each pusher has concentric side surfaces that conform to thecurvature of the staple channel in which it resides.

According to another aspect of the invention, a surgical stapler isprovided. The surgical stapler includes a handle assembly connected to astapler cartridge assembly. The stapler cartridge assembly has an endeffector at the distal end. The end effector includes an upper jawconnected to a lower jaw such that the upper jaw is movable via thehandle assembly relative to the lower jaw between an open configurationand a closed configuration. Of course, either of the upper jaw and thelower jaw can be movable with respect to the other and in anothervariation, both jaws are movable. The lower jaw has an upper surface andthe upper jaw has an anvil surface. In the closed configuration, a gapis defined between the upper surface and anvil surface for receivingtissue to be stapled. The lower jaw further includes a plurality ofstaple channels arranged longitudinally along the length of the lowerjaw and configured to receive staples. Each staple channel has anopening at the upper surface. A center point and midline are defined bya cross-section taken perpendicular to the longitudinal axis of the endeffector with the jaws in a closed configuration. More than one stapleline is defined on either side of the midline by a plurality of openingsaligned along the longitudinal length of the upper surface wherein thestaple channels are curved about the center point and each staplechannel in a staple line has the same curvature and the radius ofcurvature of staple channels increases with distance toward the midline.

According to another aspect of the invention, a surgical stapler isprovided. The surgical stapler includes a handle assembly connected to astapler cartridge assembly. The stapler cartridge assembly has an endeffector at the distal end. The end effector includes an upper jawconnected to a lower jaw such that the upper jaw is movable via thehandle assembly relative to the lower jaw between an open configurationand a closed configuration. The lower jaw has an upper surface and theupper jaw has an anvil surface. In the closed configuration, a gap isdefined between the upper surface and anvil surface for receiving tissueto be stapled. The lower jaw further includes a plurality of staplechannels arranged longitudinally along the length of the lower jaw andconfigured to receive staples. Each staple channel has an opening at theupper surface. A center point and midline are defined by a cross-sectiontaken perpendicular to the longitudinal axis of the end effector withthe jaws in a closed configuration. More than one staple line is definedon either side of the midline by a plurality of openings aligned alongthe longitudinal length of the upper surface wherein the staple channelsare curved about the center point and each staple channel has the samecurvature about the center point.

According to another aspect of the invention, a surgical stapler isprovided. The surgical stapler includes a handle assembly connected to astapler cartridge assembly. The stapler cartridge assembly has an endeffector at the distal end. The end effector includes an upper jawconnected to a lower jaw such that the upper jaw is movable via thehandle assembly relative to the lower jaw between an open configurationand a closed configuration. The lower jaw has an upper surface and theupper jaw has an anvil surface. In the closed configuration, a gap isdefined between the upper surface and anvil surface for receiving tissueto be stapled. The lower jaw further includes a plurality of staplechannels arranged longitudinally along the length of the lower jaw andconfigured to receive staples. Each staple channel has an opening at theupper surface. A center point and midline are defined by a cross-sectiontaken perpendicular to the longitudinal axis of the end effector withthe jaws in a closed configuration. At least one additional point isdefined within a cross-section taken perpendicular to the longitudinalaxis of the end effector with the jaws in a closed configuration. The atleast one additional point is not a center point. More than one stapleline is defined on either side of the midline by a plurality of openingsaligned along the longitudinal length of the upper surface wherein oneor more staple channels are curved about the center point or the atleast one additional point. In another variation, one or more staplechannels are elliptical about the center point or the at least oneadditional point. In another variation, the stapler further includes aplurality of staples disposed inside the staple channels and each staplehas curved legs that conform to the curvature of the staple channels inwhich they reside. In another variation, the stapler further includes aplurality of pushers disposed inside the staple channels that areconfigured to contact and eject staples and each pusher has concentricside surfaces that conform to the curvature of the staple channel inwhich it resides. In another variation, one or more staple channels arecurved about the center point or the at least one additional point andperpendicular to the upper surface. In another variation, one or morestaple channels are elliptical about the center point or the at leastone additional point and perpendicular to the upper surface. In anothervariation, one or more staple channels are curved about the center pointor the at least one additional point and oblique to the upper surface.In another variation, one or more staple channels are curved about thecenter point or the at least one additional point and lie in a planehaving a compound angle to the upper surface.

According to another aspect of the invention, a surgical stapler isprovided. The surgical stapler includes a handle assembly connected to astapler cartridge assembly. The stapler cartridge assembly has an endeffector at the distal end. The end effector includes an upper jawconnected to a lower jaw such that the upper jaw is movable via thehandle assembly relative to the lower jaw between an open configurationand a closed configuration. The lower jaw has an upper surface and theupper jaw has an anvil surface. In the closed configuration, a gap isdefined between the upper surface and anvil surface for receiving tissueto be stapled. The lower jaw further includes a plurality of staplechannels arranged longitudinally along the length of the lower jaw andconfigured to receive staples. Each staple channel has an opening at theupper surface. A center point and midline are defined by a cross-sectiontaken perpendicular to the longitudinal axis of the end effector withthe jaws in a closed configuration. The staple channels are curved aboutthe center point wherein the upper surface of the lower jaw is angledrelative to the midline plane toward the anvil surface. In anothervariation, the upper surface and anvil surface are angled andsubstantially parallel. In another variation, the upper surface of thelower jaw is concave toward the anvil surface. In another variation, theupper surface is bifurcated such that the upper surface forms twosurfaces having an acute angle therebetween. In another variation, theupper surface is bifurcated such that the upper surface forms twosurfaces with the apex of the angle being substantially at the midline.In another variation, the upper surface forms three surfaces such thattwo surfaces have an acute angle therebetween and are interconnected bya third surface defining a chord in the cross-section takenperpendicular to the longitudinal axis.

According to another aspect of the invention, a surgical stapler isprovided. The surgical stapler includes a handle assembly connected to astapler cartridge assembly. The stapler cartridge assembly has an endeffector at the distal end. The end effector includes an upper jawconnected to a lower jaw such that the upper jaw is movable via thehandle assembly relative to the lower jaw between an open configurationand a closed configuration. The lower jaw has an upper surface and theupper jaw has an anvil surface. In the closed configuration, a gap isdefined between the upper surface and anvil surface for receiving tissueto be stapled. The lower jaw further includes a plurality of staplechannels arranged longitudinally along the length of the lower jaw andconfigured to receive staples. Each staple channel has an opening at theupper surface. A center point is defined by a cross-section takenperpendicular to the longitudinal axis of the end effector with the jawsin a closed configuration and the staple channels are curved about thecenter point. The surgical stapler further includes a plurality ofstaples disposed inside the staple channels. Each staple has a base withupwardly extending legs. Each staple has an undeformed configuration inwhich the staple legs are curved to conform to the curvature of thestaple channels in which they reside and a deformed configuration inwhich the staple legs are closed to capture tissue. Actuation of thestapler at the handle assembly moves staples from the undeformedconfiguration inside the channel against the anvil surface into thedeformed configuration. In one variation, each staple has two legs. Inanother variation, each staple has two legs and the stapler isconfigured such that one leg contacts the anvil surface before the otherleg. In one variation, each staple has four legs. In one variation, eachstaple has four staple legs and the stapler is configured such that twolegs contact the anvil surface before the remaining two legs. In anothervariation, the staple includes two or four legs and all of the legs arebent to the same side in the deformed configuration. In anothervariation, the staple includes two or four legs and the staple base isaligned parallel to the longitudinal axis and the staple legs arealigned substantially perpendicular to the longitudinal axis in thedeformed configuration. In another variation, the staple includes twolegs and the staple forms a substantial B-shaped deformed configuration.In another variation, the staple includes two legs and the staple legsform two open circles. In another variation, the staple includes twolegs and the staple legs form two open circles residing in two planesthat are parallel to each other and also perpendicular to the base ofthe staple. In another variation, the staple includes two legs and thestaple legs and base are aligned parallel to the longitudinal axis inthe deformed configuration.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a cross-sectional schematic view of a distal end of aconventional surgical stapler.

FIG. 1B is a cross-sectional schematic view of a distal end of aconventional surgical stapler with a smaller diameter.

FIG. 2A is a top sectional schematic view of tissue with staples formingstaple lines delivered with the stapler of FIG. 1A.

FIG. 2B is a top sectional schematic view of tissue with staples formingstaple lines delivered with the stapler of FIG. 1B.

FIG. 3 is a top perspective view of a surgical stapler according to thepresent invention.

FIG. 4 is a side view of a stapler cartridge assembly according to thepresent invention.

FIG. 5 is semi-transparent side view a proximal end of a staplercartridge assembly according to the present invention.

FIG. 6 is side view of an actuator shaft and I-beam slider according tothe present invention.

FIG. 7 is a top perspective view of an I-beam slider according to thepresent invention.

FIG. 8 is a side view of an I-beam slider according to the presentinvention.

FIG. 9 is a top view of an I-beam slider according to the presentinvention.

FIG. 10 is a bottom view of an I-beam slider according to the presentinvention.

FIG. 11 is a front view of an I-beam slider according to the presentinvention.

FIG. 12 is a rear view of an I-beam slider according to the presentinvention.

FIG. 13 is a semi-transparent, top perspective view of an end effectorwith jaws in an open position according to the present invention.

FIG. 14 is a top perspective view of an end effector with jaws in anopen position according to the present invention.

FIG. 15 is a side view of an end effector with jaws in an open positionaccording to the present invention.

FIG. 16 is a semi-transparent, cross-sectional view of an end effectorwith jaws in a closed position according to the present invention.

FIG. 17 is a perspective view of a pusher according to the presentinvention.

FIG. 18 is a side view of a pusher according to the present invention.

FIG. 19 is a side view of a pusher according to the present invention.

FIG. 20 is an end view of a pusher according to the present invention.

FIG. 21 is an end view of a pusher according to the present invention.

FIG. 22 is a top view of a pusher according to the present invention.

FIG. 23 is a bottom view of a pusher according to the present invention.

FIG. 24 is a top perspective view of a staple according to the presentinvention.

FIG. 25 is a side view of a staple according to the present invention.

FIG. 26 is an end view of a staple according to the present invention.

FIG. 27 is a top view of a staple according to the present invention.

FIG. 28 is a top perspective view of a deformed staple according to thepresent invention.

FIG. 29 is a side view of a deformed staple according to the presentinvention.

FIG. 30 is an end view of a deformed staple according to the presentinvention.

FIG. 31 is a top perspective view of a staple according to the presentinvention.

FIG. 32 is a side view of a staple according to the present invention.

FIG. 33 is an end view of a staple according to the present invention.

FIG. 34 is a top perspective view of a deformed staple according to thepresent invention.

FIG. 35 is a side view of a deformed staple according to the presentinvention.

FIG. 36 is an end view of a deformed staple according to the presentinvention.

FIG. 37 is a top perspective view of a staple according to the presentinvention.

FIG. 38 is a side view of a staple according to the present invention.

FIG. 39 is an end view of a staple according to the present invention.

FIG. 40 is a top view of a staple according to the present invention.

FIG. 41 is a top perspective view of a deformed staple according to thepresent invention.

FIG. 42 is a side view of a deformed staple according to the presentinvention.

FIG. 43 is a top view of a deformed staple according to the presentinvention.

FIG. 44 is a partially transparent, cross-sectional view of an endeffector according to the present invention.

FIG. 45 is a partially transparent, cross-sectional view of an endeffector according to the present invention.

FIG. 46 is a partially transparent, cross-sectional view of an endeffector according to the present invention.

FIG. 47 is a side cross-sectional view of an end effector according tothe present invention.

FIG. 48 is a top sectional view of an end effector according to thepresent invention.

FIG. 49 is a top perspective, sectional view of an end effectoraccording to the present invention.

FIG. 50 is a top perspective view of a two-pronged staple according tothe present invention.

FIG. 51 is a side view of a two-pronged staple according to the presentinvention.

FIG. 52 is an end view of a two-pronged staple according to the presentinvention.

FIG. 53 is a top view of a two-pronged staple according to the presentinvention.

FIG. 54 is a top perspective view of a deformed two-pronged stapleaccording to the present invention.

FIG. 55 is a side view of a deformed two-pronged staple according to thepresent invention.

FIG. 56 is an end view of a deformed two-pronged staple according to thepresent invention.

FIG. 57 is a partially transparent, cross-sectional view of an endeffector according to the present invention

FIG. 58 is a partially transparent, cross-sectional view of an endeffector according to the present invention.

FIG. 59 is a partially transparent, cross-sectional view of an endeffector according to the present invention.

FIG. 60 is a partially transparent, sectional, top-perspective view ofan end effector according to the present invention.

FIG. 61 is a partially transparent, side sectional view of an endeffector according to the present invention.

FIG. 62 is a top sectional view of an end effector according to thepresent invention.

FIG. 63 is a semi-transparent, top perspective view of an end effectoraccording to the present invention.

FIG. 64 is a cross-sectional view of an end effector according to thepresent invention.

FIG. 65 is a cross-sectional view of an end effector according to thepresent invention.

FIG. 66A is a cross-sectional end view of an end effector according tothe present invention.

FIG. 66B is a cross-sectional end view of an I-beam according to thepresent invention.

FIG. 66C is a cross-sectional end view of an I-beam according to thepresent invention.

FIG. 66D is a cross-sectional end view of an I-beam according to thepresent invention.

FIG. 67 is a top sectional view of an end effector according to thepresent invention.

FIG. 68 is a cross-sectional end view of an end effector according tothe present invention.

FIG. 69 is a sectional bottom view of an end effector according to thepresent invention.

FIG. 70 is a top perspective view of an inner pusher according to thepresent invention.

FIG. 71 is a top perspective view of an inner pusher according to thepresent invention.

FIG. 72 is a top perspective view of an outer pusher and stapleaccording to the present invention.

FIG. 73 is a partial sectional, top perspective view of an end effectorshowing an I-beam slider, two inner pushers, two outer pushers and fourstaples according to the present invention.

FIG. 74 is a partial sectional, top perspective view of an end effectorshowing an I-beam slider, an inner pusher, an outer pusher and twostaples according to the present invention.

FIG. 75 is a partial sectional, top perspective view of an end effectorshowing an I-beam slider, two inner pushers, two outer pushers and fourstaples according to the present invention.

FIG. 76 is a partial sectional, side elevational view of an end effectorshowing an I-beam slider two inner pushers, an outer pusher and threestaples according to the present invention.

FIG. 77 is a partial sectional, bottom view of an end effector showingan I-beam slider two inner pushers, two outer pushers and four staplesaccording to the present invention.

FIG. 78 is a front elevational view of a staple according to the presentinvention.

FIG. 79 is a side elevational view of a staple according to the presentinvention.

FIG. 80 is a top perspective view of a deformed staple according to thepresent invention.

FIG. 81 is top perspective view of a deformed staple according to thepresent invention.

FIG. 82 is a front elevational view of a deformed staple according tothe present invention.

FIG. 83 is a top view of a deformed staple according to the presentinvention.

FIG. 84 is a side elevational view of a deformed staple according to thepresent invention.

FIG. 85 is a top perspective view of a staple according to the presentinvention.

FIG. 86 is a top perspective view of a staple according to the presentinvention.

FIG. 87 is a front elevational view of a staple according to the presentinvention.

FIG. 88 is a top view of a staple according to the present invention.

FIG. 89 is a side view of a staple according to the present invention.

FIG. 90 is a top perspective view of a deformed staple according to thepresent invention.

FIG. 91 is a top view of a deformed staple according to the presentinvention.

FIG. 92 is a side elevational view of a deformed staple according to thepresent invention.

FIG. 93 is a front elevation view of a deformed staple according to thepresent invention.

FIG. 94 is a schematic of a cross-sectional view of a lower jaw andstaple.

FIG. 95 is a schematic of a cross-sectional view of a lower jaw andstaple according to the present invention.

FIG. 96 is a schematic of a cross-sectional view of a lower jaw andstaple according to the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIG. 3, there is shown a perspective view of a surgicalstapler 10 according to the present invention. The stapler 10 iscomprised of a handle assembly 12 removably connected to a staplercartridge assembly 14. The handle assembly 12 is configured to controlthe instrument and actuate the deployment of staples located in thedistal end of the stapler cartridge assembly 14. After the staples havebeen expended from the stapler 10, the stapler cartridge assembly 14 isremoved from the handle assembly 12 and a new stapler cartridge assembly14 is connected to the handle assembly 12 for continued stapling. In analternative variation, a separate staple cartridge is replaceable fromthe distal end of the stapler cartridge assembly 14 for continuedstapling.

Turning to FIG. 4, the stapler cartridge assembly 14 will now bediscussed in detail. The stapler cartridge assembly 14 includes aconnector 16 at the proximal end and an end effector 18 at the distalend. An outer tube 20 is connected to the end effector 18 at the distalend and to the connector 16 at the proximal end. An actuator shaft 22 isdisposed inside the lumen of the outer tube 20. The outer tube 20 issubstantially cylindrical having an outer diameter of approximately 5-10mm. The actuator shaft 22 is configured to slide longitudinally relativeto the outer tube 20. Detail of the proximal end of the staplercartridge assembly 14 is shown in FIG. 5.

Turning to FIG. 5, the proximal end of the stapler cartridge assembly 14is shown. The connector 16 includes a bolt 24 that extends laterallyoutwardly from the outer surface of the connector 16. A similar bolt 24extends on the opposite side of the connector 16 and is not visible inFIG. 5. The bolt 24 is configured for a bayonet-like connection with thehandle assembly 12 of the stapler 10 that includes a complementary slotfor receiving the bolt 24 to secure the cartridge assembly 14 to thehandle assembly 12. FIG. 5 also illustrates the actuator shaft 22 movedproximally relative to the outer tube 20 when compared to FIG. 4 inwhich the actuator shaft 22 is shown to be moved more distally relativeto the outer tube 20. As seen in FIG. 5, the proximal end of theactuator shaft 22 includes a bolt 26 that extends laterally outwardlyfrom the actuator shaft 22. The bolt 26 is configured for a bayonet-likeconnection with an actuator shaft of the handle assembly 12 whichincludes a complementary slot for receiving the bolt 26. Mating the bolt24 of the connector 16 to handle assembly 12 simultaneously mates thebolt 26 of the actuator shaft 22 to the actuator shaft of the handleassembly 12. When connected to the handle assembly 12, the handleassembly 12 is used to move the actuator shaft 22 forward and backwardinside the outer tube 20 to effect opening and closing of the distaljaw-like members and the deployment of staples.

Turning to FIG. 6, the actuator shaft 22 will now be described. Theactuator shaft 22 is an elongated shaft having a substantiallycylindrical proximal portion 28 having actuator bolts 26 at the proximalend for connection with the actuator of the handle assembly 12. Thesubstantially cylindrical portion 28 is sized for a concentric close fitinside the lumen of the outer tube 20. The cylindrical portion 28 isconnected with pins to an extended I-beam portion 30 toward the distalend of the actuator shaft 22. The distal end of the actuator shaft 22includes an I-beam 32 connected to the extended I-beam portion 30.

Turning now to FIGS. 7-12, the I-beam 32 will now be described. TheI-beam 32 includes a top portion 34 and a bottom portion 36interconnected by a middle portion 38. The top portion 34 includes abeveled front end 40 and a curved top. The middle portion 38 includes ablade 42 which would include a sharp leading edge that is shown as ablunt surface in FIGS. 7-12. At the back end, the middle portion 38includes a portion 46 for connecting with the extended I-beam portion 30as shown in FIG. 6. The bottom portion 36 leads the front end of theI-beam 32 and includes a curved bottom with a convex outer surface and aleading surface 44 that resembles a snowplow. The leading surface 44includes two converging surfaces that meet at a vertical line or tip.Each converging surface extends outwardly from the tip in a helicalspiral fashion, that is, it not only extends upwardly, but also, spiralsor curves or rotates with respect to the longitudinal axis of the I-beam32 to create the helix wedge design. The front-elevational view of theI-beam is shown in FIG. 11 which illustrates the profile to besubstantially in the shape of a capital letter “I” having a lower curvedportion. The I-beam slides longitudinally inside the end effector 18 andas such may be called a slider. The I-beam/slider 32 is configured tourge staples out of the end effector 18 via the leading surface 44.

Turning now to FIGS. 13-16, the end effector 18 will be described. Theend effector 18 includes an upper jaw 48 hinged to a lower jaw 50. Whenthe jaws 48, 50 are in a closed orientation, they form a substantiallycircular cross-section when viewed from the end. The lower jaw 50includes a staple housing or staple cartridge 52 containing a pluralityof staples 54. The lower jaw 50 comprises a hollow semi-cylindricalshell or outer lower jaw 51 and a conformingly-shaped inner lower jaw orcartridge 52 disposed inside the outer lower jaw 51. The inner lower jaw52 may or may not be removable and replaceable like a cartridge forintroducing more staples 54 for continued firing. In a variation inwhich the inner lower jaw 52 is fixed, the entire stapler 10 isdisposable after a single firing or, alternatively, the staplercartridge assembly 14 serves as a disposable cartridge and is removedand replaced for continued firing. The inner lower jaw 52 includes aplurality of channels 53 or staple pathways configured to receivestaples 54 and serve as a guide for delivering the staples 54 towardsthe upper jaw 48. Each channel 53 forms a top opening at the top surfaceof lower jaw 50 through which a staple 54 exits the lower jaw 50. Theinner lower jaw 52 includes a central channel 55 that extendslongitudinally and is configured to receive a longitudinally-translatingI-beam 32. The bottom of the inner lower jaw 52 is spaced from the outerlower jaw 51 to form a gap that is conformingly-shaped to receive thebottom portion 36 of the I-beam 32 as it translates longitudinally. Eachchannel 53 extends between the top opening and a bottom opening. Thebottom opening is in communication with the gap between the inner andouter lower jaw. Each channel 53 is curved and transcribes an arcbetween the top opening of the channel and the bottom opening of thechannel as shown in FIG. 16. In a cross-section taken perpendicular tothe longitudinal axis of the end effector 18, the channel 53 has aradius of curvature that substantially matches the radius of curvatureof the outer lower jaw 51 and forms a circumferential delivery pathwayfor the staple. In one variation, the channels 53 are concentric aboutthe center point of a cross-section taken perpendicular to thelongitudinal axis of the closed jaws 48, 50. A four-pronged staple 54 isshown residing in the channel 53 in FIG. 13. A pusher 58 is alsodisposed inside each channel 53. Two pushers 58 are slightly visible inFIG. 16. The pusher 58 is configured to contact the leading surface 44of the I-beam slider 32 and in turn contact at least one staple 54.

Turning to FIGS. 17-23, there is shown a pusher 58 according to thepresent invention. The pusher 58 is a wedge-shaped object configured forinterfacing between the I-beam slider 32 and one or more staples 54. Thepusher 58 includes a top surface 60 and a bottom surface 62interconnected by two side surfaces 64, 66 and two end surface 68, 70.The bottom surface 62 includes an I-beam slider contacting surface 72configured to contact the leading surface 44 of the I-beam slider 32.The I-beam slider contacting surface 72 is shaped to conform to theleading surface 44. If the leading surface 44 of the I-beam slider 32 ishelical in shape as described above, then the contacting surface 72 isalso helical. The top surface 60 is configured to contact one or morestaples 54 and as such comprises a staple contacting surface. Both thetop surface 60 and the bottom surface 62 including the contactingsurface 72 is slightly angled with respect to side surface 66 andconverge slightly towards side surface 64. As can be seen in FIG. 21,the side surface 64 is slightly concave and the opposite side surface 66is slightly convex. Both side surfaces 64, 66 are concentric withrespect to each other. In one variation, the side surfaces 64, 66 areconcentric with respect to the center point of a cross-section takenperpendicular the longitudinal axis of the jaws 48, 50 with the jaws 48,50 in a closed configuration. In one variation, the side surfaces 64, 66have a curvature that substantially matches the curvature of the channel53 in which it resides. In one variation, the channel 53 iscircumferential to a cross-section perpendicular to the longitudinalaxis of the jaws 48, 50 with the jaws 48, 50 in a closed configurationand the side surfaces 64, 66 of the pusher substantially match thecircumferential curvature. The end surfaces 68 and 70 are substantiallyparallel and perpendicular. When urged by the I-beam slider 32, eachpusher 58 contacts a staple 54 and travels smoothly within itsrespective channel 53.

Referring back to FIGS. 13-16, the upper jaw 48 will now be described.The upper jaw 48 is substantially semi-cylindrical in shape to conformto a cylindrical lumen of a cannula in which it is inserted. The upperjaw 48 includes a central slot 76 that extends longitudinally. Thecentral slot 76 is conformingly shaped and configured to receive the topportion 34 of the I-beam 32 and at least a portion of the narrowermiddle portion 38 of the I-beam 32 such that the I-beam 32 is capable oflongitudinal movement relative to the upper jaw 48 inside and along thecentral slot 76. The central slot 76 includes an open proximal end whichis ramped and configured to cam against the beveled front end 40 of theI-beam 32. The upper jaw 48 is spring biased in an open orientation withrespect to the lower jaw 50 and as the beveled front end 40 of theI-beam 32 enters the central slot 76, and in particular, the top portion34 enters the wider upper end of the central slot 76, the upper andlower jaws 48, 50 are forced to close. Back and forth movement of theI-beam 32, into and out of the central slot 76 or against the proximalopening of the central slot 76, opens and closes the end effector 18allowing the user to grasp and release tissue and reposition the stapler10. With the end effector 18 in the closed configuration, the I-beam 32is capable of further longitudinal translation within the central slot76. Following the ejection of staples 54, the I-beam 32 is retractedproximally via the handle assembly 12 and as the I-beam 32 exits thecentral slot 76 the spring biased upper jaw 48 moves into an openorientation. Following the ejection of staples 54 and retraction of theI-beam 32, repeated forward translation of the I-beam 32 inside thecentral slot 76 is prevented by a lock-out mechanism to avoidinadvertent use of an already-fired cartridge.

Also, with reference to FIGS. 44-46, the upper jaw 48 further includesan inner anvil surface 74 or plate that faces and is spaced apart fromthe lower jaw 50 when in the closed position. The anvil surface 74 isconfigured to receive the legs of a staple 54 and guide, deflect,angulate, bend, crimp or clinch the staple legs as the staple is urgedthrough tissue against the anvil surface 74. To facilitate the formationof staples 54 to secure tissue, a plurality of staple-forming pockets asshown in FIGS. 44-46 are included in the anvil surface 74. These surfaceformations of a typical anvil aid in the deformation of the staple as itis deployed to achieve proper staple closure. The staple-forming pocketsare aligned with the exit openings of channels 53 in the lower jaw 50.Any misalignment between the staple-forming pockets and the ejectingstaple leads to the staples missing the staple forming pockets and mayresult in catastrophic failure of the staple line. The staple-formingpockets generally include two adjacent staple leg forming cups having acurved or sloped channeling surface formed around the perimeter of eachof the staple forming cups. The two adjacent staple leg forming cupsform a dog bone shape that facilitates the formation of consistentB-shaped staples from generally square-cornered U-shaped undeformedstaples. If four-pronged staples are deployed then the anvil surface 74includes four adjacent staple forming cups aligned with the ejectingstaple legs. Separate staple-forming pockets are provided at each stapleforming location opposite the cartridge channels 53 of the lower jaw 50.

Referring now to FIGS. 24-27, a staple 54 according to the presentinvention will be described. The staple 54 is a four-pronged staple 54shown in its undeformed or open condition. The four-pronged staple 54includes two longer first legs 78A, 78B and two shorter second legs 80A,80B interconnected by a base 82. The two longer first legs 78A, 78B arestaggered with respect to the two shorter second legs 80A, 80B such thatwhen deformed or closed against the anvil surface 74, the first legs78A, 78B do not contact the adjacent second legs 80A, 80B. The base 82serves as a caming surface for engagement with a pusher 58. The longerand shorter legs 78A, 78B, 80A, 80B all extend upwardly from the base 82and curve to one side. In one variation, the longer legs 78A, 78B areconcentric with the shorter legs 80A, 80B. In one variation, the legs78A, 78B, 80A, 80B are concentric with respect to the center point of across-section taken perpendicular the longitudinal axis of the jaws 48,50 with the jaws 48, 50 in a closed configuration. In one variation, thelegs 78A, 78B, 80A, 80B have a curvature that substantially matches thecurvature of the channel 53 in which the staple 54 resides. As seen inFIG. 26, the legs 78A, 78B, 80A, 80B are curved to the right with eachleg having a concave surface and a convex surface interconnected by twoside surfaces. Each leg 78A, 78B, 80A, 80B is angled in the samedirection with respect to the base 82. Each leg intersects with the base82 and, at the point of intersection, a notch 84 is formed in the base82 on one or more sides of each leg for manufacturing purposes. The twoside surfaces of each leg converge to form a sharp tip at a lineintersection at the free distal end of the leg. Each of the legs 78A,78B, 80A, 80B has their respective tip 86A, 86B, 88A, 88B. The tipbegins where the side surfaces begin to taper or decrease incross-sectional area in the direction distally along the leg. The tips86A, 86B, 88A, 88B may be formed in any manner and may have any othergeometric shape that is suitable for puncturing and penetrating tissuethrough which the staple is delivered.

Still referencing FIGS. 24-27, the longer first legs 78A, 78B areapproximately 0.097 inches long and the shorter second legs 80A, 80B areapproximately 0.050 inches long having a central angle with respect tothe base of approximately 60 degrees. The ratio of the shorter secondlegs 80A, 80B to the longer first legs 78A, 78B is approximately ½. Theoverall length of the base 82 is approximately 0.100 inches and in onevariation each leg 78A, 78B, 80A, 80B is concentric about the centerpoint of a cross-section taken perpendicular to the longitudinal axis ofthe jaws 48, 50 in a closed orientation. The radius of curvature of theouter surface of the first longer legs 78A, 78B is approximately 0.115inches. The radius of curvature of the outer surface at theintersections with the base 82 is approximately 0.009 inches. The radiusof curvature of the inner surface of the second shorter legs 80A, 80B isapproximately 0.065 inches. The distance between the side surfaces orthickness of the legs is approximately 0.010 inches. The distancebetween the inner surface and the outer surface or width of the legs isapproximately 0.015 inches.

Turning now to FIGS. 28-30, there is shown the staple 54 of FIGS. 24-27in a second or deformed configuration after complete actuation of thestapler. Deployment of the four-pronged staple 54, which will bediscussed in greater detail below, results in the shorter legs 80A, 80Bcontacting the anvil surface 74 and being deformed. The shorter legs80A, 80B are deflected vertically downwardly toward the base 82 andlaterally away from the base 82, away from the longitudinal axis of thestaple 54. The shorter legs 80A, 80B bend to form a curl having aC-shape with the tips 88A, 88B pointing substantially downwardly. Thetips 88A, 88B are not located above the base 82 in the deformedconfiguration. The longer legs 78A, 78B will contact the anvil surface74 and with continued movement of the slider 32 will deform such thatthe longer legs 78A, 78B are deflected vertically downwardly andlaterally toward the longitudinal axis of the base 82. The longer legs78A, 78B bend to form a deeper curl relative to the deformed shorterlegs 80A, 80B. Also, the tips 86A, 86B of the longer legs 78A, 78B arevertically closer to the base 82 than the tips 88A, 88B of the shorterlegs 80A, 80B. The tips 86A, 86B of the longer legs 78A, 78B areresident above the base 82 in the deformed configuration. All of thelegs 78A, 78B, 80A, 80B are deflected in the same direction. Forexample, as shown in the end view of FIG. 30, the legs 78A, 78B, 80A,80B are deflected toward the right. Pockets in the anvil surface 74 thatare aligned with the exit opening in the top surface of the lower jaw,guide and aid in the proper deformation of a staple.

A four-pronged staple 54 having a narrower base 82 is shown in anundeformed or open configuration in FIGS. 31-33 where like referencenumbers are used to describe like parts. In this variation of the staple54, the base 82 is approximately 0.020 inches wide and approximately0.100 inches in length. The lateral distance between the inner surfaceof longer legs 78A, 78B and the inner surface of the shorter legs 80A,80B is substantially the same as the staple 54 shown in FIGS. 24-30.Therefore, it will fit inside the same sized channel 53 and the base 82is configured to cam against the pusher 58. The staple 54 of FIGS. 31-33has an inside bend radius at the legs 78A, 78B, 80A, 80B thatsubstantially matches the thickness of the base 82. The legs 78A, 78B,80A, 80B are curved in the same manner. FIGS. 34-36 show the staple 54in a second or deformed configuration after complete actuation of thestapler. Deployment of the four-pronged staple 54 results in the shorterlegs 80A, 80B contacting the anvil surface 74 and being deformed. Theshorter legs 80A, 80B are deflected vertically downwardly toward thebase 82 and laterally away from the base 82, away from the longitudinalaxis of the staple 54. The shorter legs 80A, 80B bend to form a curlhaving a C-shape with the tips 88A, 88B pointing substantiallydownwardly. The longer legs 78A, 78B will contact the anvil surface 74and with continued movement of the slider 32 will deform such that thelonger legs 78A, 78B are deflected vertically downwardly toward the base82 and laterally toward the longitudinal axis of the base 82. The longerlegs 78A, 78B bend to form a larger deeper curl relative to the deformedshorter legs 80A, 80B. Also, the tips 86A, 86B of the longer legs 78A,78B are vertically closer to the base 82 than the tips 88A, 88B of theshorter legs 80A, 80B. The longer legs 78A, 78B have a larger radius ofcurvature relative to the shorter legs 80A, 80B. All of the legs 78A,78B, 80A, 80B are deflected in the same direction. For example, all ofthe legs 78A, 78B, 80A, 80B are deflected to the right side or to theright of the staple longitudinal axis when viewed from the end in FIG.36. Because of the narrower base 82, the tips 86A, 86B, 88A, 88B areresident to the right of the base 82 and are not located above the base82. Pockets in the anvil surface 74 that are aligned with the exitopening in the top surface of the lower jaw, guide and aid in the properdeformation of a staple.

Turning now to FIGS. 37-40, another staple 54 according to the presentinvention will be described using like reference numbers to describelike parts. The staple 54 is a four-pronged staple 54 shown in itsundeformed or open configuration and is substantially similar to thestaple 54 of FIGS. 24-30. The four-pronged staple 54 includes two longerfirst legs 78A, 78B and two shorter second legs 80A, 80B interconnectedby a base 82. The two longer legs 78A, 78B are staggered with respect tothe two shorter second legs 80A, 80B. Each of the legs 78A, 78B, 80A,80B has their respective tip 86A, 86B, 88A, 88B. The staple 54 of FIGS.37-40, further includes a plurality of leg notches 90 formed in the legs78A, 78B, 80A, 80B. The leg notches 90 extend inwardly from the sidesurfaces of the legs to create stress concentrations such that whendeflected against the anvil surface 74, the legs will tend to bend inthe location of the leg notches 90. Along the length of a leg, at leastone pair of leg notches 90 is formed wherein each leg notch 90 of thepair is located opposite from each other and at the same height withrespect to the base 82. The longer legs 78A, 78B are shown to have threepairs of leg notches 90A, 90B and 90C. The first pair of leg notches 90Ais located just beneath the tip 86A and two other pairs of leg notches90B, 90C are located further down along each leg 78A, 78B. The shortersecond legs 80A, 80B are each formed with a single pair of leg notches90D located just below the tip 88. The leg notches 90 are configuredsuch that deployment of the staple 54 against the anvil surface 74 formsa predetermined deformed configuration as depicted in FIGS. 41-43. Thelegs are shown bent in the location of the notches 90 to form segmentedC-shaped curls wherein portions of the leg between the leg notches 90define segments of the deformed configuration. In the deformedconfiguration, all of the legs 78A, 78B, 80A, 80B are bent in the samedirection with the shorter legs 80A, 80B being deflected laterally awayfrom longitudinal axis of the staple 54 and the longer legs 78A, 78Bbeing deflected toward the longitudinal axis with the tips 86A, 86B,88A, 88B being deflected vertically downwardly into tissue. Thesegmented deflection along the leg notches 90 helps in angulating thesharp tips into penetrating tissue as well as in creating a deformedstaple height that can accommodate tissue inside the staple 54 withoutsevering the tissue arising from uneven deformation. The leg notches 90provide a C-shaped curvature in the legs that is consistently andreliably formed.

In any of the staple variations, the staple legs 78A, 78B, 80A, 80B mayinclude at least one barb or lateral hook-like protrusion. The at leastone barb may be provided anywhere along the length of the leg includingnear the distal end of each leg and formed in side surfaces. Barbsassist in providing an increased mechanical hold of the staple intotissue and can be formed on any or all of the four legs and on the innersurface, outer surface and/or side surfaces. In one variation, at leastone barb is formed in the inner surface of the longer first legs 78A,78B and the outer surface of the shorter second legs 80A, 80B. Multiplebarbs along one or more of the legs are also possible as are smallerbarbs such as micro and nano-sized barbs.

The staples 54 may be formed attached to a backbone in a fishbone stylefor ease of manufacturing, assembly and handling. A sheet or block ofmetal such as surgical steel, stainless steel, or titanium is providedand a plurality of staples 54 is cut into the sheet of metal on a wireelectrical discharge machining (EDM) machine. The staples 54 may also beformed utilizing a micro-water jet, photo etching or by stamping. Thestaples 54 may be formed with bent legs or the bending of the legs isperformed in a separate step. The staples 54 remain connected to thebackbone via narrow connecting tabs until the staples 54 are broken offat the tabs and then loaded into a staple cartridge. After a staple 54is broken off, a portion of the connecting tab may remain attached tothe staple 54. The remnant tab may advantageously serve as a barb forincreasing mechanical holding onto tissue captured inside a closedstaple 54 after deployment. Also, the backbone can be an aid in thestorage of staples 54 and in the assembly of staple cartridges.

A staple cartridge in the form of a single unit is inserted into astaple cartridge receiving portion of the lower jaw 50. The staplecartridge may also be in the form of two units with each unit having twoslots to be loaded on either side of the central lower jaw channel 55.Each cartridge can include a cover slip of paper (not shown) coveringthe staple channels 53 to retain the staples 54 during storage andhandling. The cover slip is then removed by peeling away just prior toor after installation of the cartridge. Each staple cartridge may alsocontain an I-beam 32 and pushers 58 disposed inside the cartridge. Inanother variation of the cartridge, the staple cartridge ispre-installed inside the stapler cartridge assembly 14 and after thestaples 54 are expended the entire stapler cartridge assembly 14 isremoved and disposed and a new stapler cartridge assembly 14 isconnected to the handle assembly 12 for continue stapling. With thestaple cartridge assembly 14 connected to the handle assembly 12, theactuator shaft 22 connects to an actuator shaft inside the handleassembly 12. The handle assembly 12 is then used to operate the stapler10 in three different functions or modes of operation. The first modeallows the user to open and close the jaws 48, 50 of the end effector18. The second mode fires the staples and the third mode of operationreturns the I-beam 32 to its original proximal position following thefiring of staples. A lock-out mechanism locks the I-beam 32 preventingit from moving forward inside an already expended or partially expendedcartridge.

The handle assembly 12 includes a handle connected to a forward driverwhich engages a forward tooth on the actuator shaft 22. When the handleis depressed, the actuator is moved slightly forward which in turn movesthe actuator shaft 22 of the stapler cartridge assembly 14 forward.Since the actuator shaft 22 is connected to the I-beam 32, the I-beam 32advances forward with the depression of the handle. As the I-beam 32advances, the beveled front end 40 of the top portion 34 of the I-beam32 enters the passageway or central slot 76 in the upper jaw 48 whichdeflects the open and spring biased upper jaw 48 downward from an openposition to a closed position. The upper jaw 48 is connected to thelower jaw 50 with a pin such that the upper jaw 48 pivots with respectto the lower jaw 50. Springs are included to create a spring bias thaturges the upper jaw 48 in an open position with respect to the lower jaw50. When the handle is released the actuator shaft 22 moves proximallypulling the I-beam 32 also proximally allowing the spring bias to openthe jaws as the top portion 34 of the I-beam exits the passageway 76.The user can open and close the jaws of the end effector 18 by pressingand releasing the handle 12 to position the targeted tissue between theupper and lower jaws of stapler 10. In a closed position, the distanceacross the gap between the upper jaw 48 and lower jaw 50 isapproximately 0.030-0.060 inches.

After the jaws are closed in position at the targeted tissue location,the stapler 10 is switched to operate in fire mode by depressing a firebutton on the handle assembly 12. The fire button disengages an opendriver from the actuator shaft freeing it for longitudinal movement. Theopen driver is engaged with the teeth of the actuator shaft. The opendriver disengages from the teeth of the actuator shaft with the firebutton depressed. With the open driver disengaged, the trigger handleswings out and the forward driver engages with forward teeth on theactuator shaft. Depressing the handle advances the actuator shaftforward as the forward driver freely engages teeth with each squeeze ofthe trigger handle. The handle is squeezed multiple times to advance theI-beam 32 all the way to the distal end of the end effector 18.Actuation is described in co-pending U.S. Provisional Patent Applicationbearing Ser. No. 61/785,100 filed on Mar. 14, 2013 and entitled“Surgical stapler with partial pockets” and hereby incorporated byreference in its entirety.

FIGS. 44-46 are semi-transparent cross-sectional views of the endeffector 18 with the jaws 48, 50 in a closed position takenperpendicular to the longitudinal axis in three progressive stages ofstaple deployment. FIG. 44 shows a pair of staples 54 residing incircumferential staple-receiving channels 53. The base 82 of each staple54 is in contact with the top surface 60 of the pusher 58. As the I-beam32 is advanced, the pusher 58 will move the staples 54 along thecircumferential pathway, upwardly and outwardly from the lower jaw 50and into the gap between the upper jaw 48 and lower jaw 50 as shown inFIG. 45. FIG. 45 illustrates the staple legs 78, 80, in particular, thetips of the legs 78, 80 approaching the anvil surface 74. The anvilsurface 74 is shown in FIG. 45 to be provided with concavestaple-forming pockets that aid in the deflection and deformation of thestaple legs 78, 80 relative to the staple base 82. Since the longerstaple legs 78 will first contact the anvil surface 74 before theshorter legs 80 contact the anvil surface 74, the deployment oractuation force required to bend the staple legs 78, 80 will beadvantageously reduced since the longer two legs 78 of the staple 54will have already been slightly deflected before contact with theshorter legs 80 is made and forced into deflection. The reduced firingforce permits smoother deployment and increased ease of actuation. Also,circumferential firing advantageously permits the stapler to include anadditional row of staples while keeping the actuation force constant.Because the staple legs 78, 80 are curved prior to deformation, theforce required to deploy the staple is advantageously reduced becausethe curved legs do not require a greater force associated with bucklingthe staple legs. The curved staple legs are simply bent into the closedconfiguration. Further advancement of the I-beam 32 in the distaldirection moves the pushers 58 on either side of the I-beam 32 togetherwith their respective staples 54 further through the circumferentialchannels 53 and upwardly against the anvil surface 74 and into adeformed configuration as shown in FIG. 46. FIG. 46 illustrates a fullyformed staple 54 residing in the gap between the upper jaw 48 and thelower jaw 50. The gap provides space for receiving the target tissue.FIGS. 47-48 illustrate a partially transparent side cross-sectional viewand a partial cross-sectional top view of the I-beam 32 being advancedalong the length of the end effector 18 with the upper and lower jaws48, 50 in a closed configuration. FIG. 47 illustrates the variouspositions of the staples 54 and pushers 58 relative to the position ofthe I-beam 32. FIG. 49 illustrates a partial sectional, top perspectiveview of the end effector 18 with the I-beam 32 advanced along thecentral lower jaw channel 55 deploying and deforming staples 54 alongthe advancement pathway. The staples 54 proximal to the bottom portion36 of the I-beam 32 are shown to be fully deformed. Staples 54 incontact with the leading surface 44 of the I-beam 32 are shown invarious stages of deployment and deformation. Staples 54 distal to theleading surface 44 of the I-beam 32 are shown resident within the staplechannels 53 prior to contact with the I-beam 32 and movement out of thechannels 53. In this variation, the staple legs 78, 80 of a four-prongedstaple are deflected in a direction that is transverse to thelongitudinal axis of the end effector 18 and also transverse to thelength of the staple base 82.

Referring now to FIGS. 50-53, a two-pronged staple 100 according to thepresent invention will be described. The two-pronged staple 100 is shownin its undeformed or open configuration. The staple 100 includes twolegs 102 interconnected by a base 104. The base 104 serves as a contactsurface for engagement with the pusher 58. The legs 102 extend upwardlyfrom the base 104 and curve to one side as can be clearly seen in FIG.52. The curvature of the staple legs 102 correspond to the curvature ofthe circumferential channels 53 into which they are disposed and alongwhich they travel as they are urged by the pushers 58 comingsequentially into contact with the I-beam 32. The curvature of thestaple legs 102, therefore, also substantially corresponds to thecircumference of the lower jaw 50. The two side surfaces of each legconverge to form a sharp tip 106 at a line intersection at the freedistal end of each leg 102. The tip 106 begins wherein the side surfacesbeing to taper or decrease in cross-sectional area in a directiondistally along the leg 102. The tip 102 may be formed in any manner andmay have any geometric shape that is suitable for puncturing andpenetrating tissue through which the staple 100 is delivered.

Still referencing FIGS. 50-53, the legs 102 are approximately 0.100inches long having a central angle of approximately 62 degrees. Theoverall length of the base 82 is approximately 0.100 inches and each leg102 is concentric about the center point of a cross-section takenperpendicular to the longitudinal axis of the jaws 48, 50 in a closedorientation. The radius of curvature of the outer surface of the firstlonger legs 78A, 78B is approximately 0.115 inches. The distance betweenthe side surfaces or thickness of the legs is approximately 0.007inches. The distance between the inner surface and the outer surface orwidth of the legs is approximately 0.020 inches.

Turning now to FIGS. 54-56, there is shown the staple 100 of FIGS. 50-53in a second or deformed configuration after complete actuation of thestapler. Deployment of the two-pronged staple 100, which will bediscussed in greater detail below, results in the legs 102 contactingthe anvil surface 74 of the upper jaw 48 and being deformed. The legs102 are deflected toward each other such that the tips 106 are angledvertically downwardly toward the base 82. The legs 102 will contact theanvil surface 74 wherein anvil pockets that are aligned with the exitopenings in the top surface of the lower jaw 50 may be formed to guidethe proper deformation of the staple legs 102. The deformed staple 100has a substantially B-shaped configuration.

FIGS. 57-59 are semi-transparent cross-sectional views of the endeffector 18 with the upper and lower jaws 48, 50 in a closed positiontaken perpendicular to the longitudinal axis in three progressive stagesof staple deployment. FIG. 57 shows four two-pronged staples 100residing in two circumferential staple-receiving channels 53 on eitherside of the I-beam 32. The base 104 of each staple 100 is in contactwith the top surface 60 of the pusher 58. As the I-beam 32 is advanced,the pusher 58 will move the staples 100 along the circumferentialpathway, upwardly and outwardly from the lower jaw 50 and into the gapbetween the upper jaw 48 and lower jaw 50 as shown in FIG. 58. FIG. 58illustrates the staple legs 102 in particular, the tips of the legs 106approaching the anvil surface 74. The anvil surface 74 is shown in FIGS.57-59 to be provided with staple-forming pockets 108 that aid in thedeflection and deformation of the staple legs 102 relative to the staplebase 104. Each staple pocket 108 includes a staple contact surface 110that is substantially perpendicular to the circumference of the staplechannels 53 such that a curved staple 100 that exits a circumferentialchannel 53 comes into contact with the staple contact surface 110 in aperpendicular orientation. Further advancement of the I-beam 32 in thedistal direction moves the pushers 58 on either side of the I-beam 32and their respective staples 100 further through the circumferentialchannels 53 and upwardly against the staple pockets 108 in the anvilsurface 74 and into a deformed configuration as shown in FIG. 59. FIG.59 illustrates a fully formed staples 100 residing in the gap betweenthe upper jaw 48 and the lower jaw 50. The gap provides space forreceiving the target tissue. FIG. 60 illustrates the end effector 18with the I-beam 32 partially advanced along the length of the endeffector 18. Two rows of two-pronged staples 100 are shown on eitherside of the I-beam 32 at various stages of deployment. The staples 100are shown emerging from the staple channels 53 in the lower jaw 50.Staples 100 that are located distally of the I-beam 32 have onlypartially emerged or have not yet emerged from the channels 32 relativeto staples 100 proximal to the I-beam 32. For clarity, the staples 100located proximally to the I-beam 32 are shown not deformed in FIG. 60;normally these staples 100 would be deformed against the anvil surface74 of the upper jaw 48. FIG. 60 illustrates two rows of staples 100configured such that the length of the staple bases 104 as well as thelength of the channels 53 are parallel to the longitudinal axis of theend effector 18. Similarly, the staple pockets 108 (not shown in FIG.60) in the upper jaw 48 are oriented parallel to the longitudinal axisof the end effector 18. The exit openings of the channels 53 areparallel and are aligned with the adjacent exit openings of the adjacentrow of exit openings. In another variation, the exit openings of thechannels 53 in the lower jaw 50 are staggered with respect to theadjacent exit openings of the adjacent row.

Turning now to FIGS. 61-63, a variation of an end effector 18 for thedeployment of two-pronged staples 100 is shown in which only one row ofstaples 100 is provided on either side of the I-beam 32 in which theI-beam 32 is advanced along the length of the end effector 18 with theupper and lower jaws 48, 50 in a closed configuration. FIG. 61illustrates staples 100 emerging from the lower jaw 50 relative to thetranslation of the I-beam 32. Deformed staples 100 are shown resident inthe gap between the upper jaw 48 and the lower jaw 50 at and proximal tothe location of the I-beam 32. Undeformed staples 100 are emerging fromor concealed in the lower jaw 50 at and distal to the location of theI-beam 32. FIG. 62 illustrates a partial sectional, top perspective viewof the end effector 18 with the I-beam 32 advanced along the centrallower jaw channel 55 deploying and deforming staples 100 along theadvancement pathway. FIGS. 61 and 63 illustrate staple pockets 108 inthe upper jaw 48 that are aligned with the staple channels 53 in thelower jaw 50. The staple pockets 108 include two adjacent concavesurfaces aligned with each exiting staple leg 102. The concave pockets108 deflect the staple legs 102 toward each other from an undeformedsubstantially U-shaped staple configuration into a deformedconfiguration forming a substantially B-shaped configuration with thestaple tips 106 pointing downward toward the staple base 104. A singlestaple line is formed on either side of the lower jaw channel 55. Thesestaple lines are parallel to the longitudinal axis of the end effector18 and the lengths of the staple bases 104 are also arranged parallel tothe longitudinal axis and I-beam channel. Additional staple lines oneither side of the central channel 55 are within the scope of thepresent invention.

As the I-beam 32 advances distally along the end effector 18, thecontacting surface 72 of the I-beam 32 will contact pushers 58 locatedin the channels 53 which in turn will contact staples 54, 100 that arealso disposed inside staple channels 53. As the I-beam 32 advances, thepushers 58 will urge the staples 54, 100 upwardly and will continue tourge them sequentially upwardly with distal translation of the I-beam32. With sufficient deployment height, the staple legs 78, 80, 102 willcome into contact with the anvil surface 74 of the upper jaw 48. Inparticular, the staple legs will contact the anvil surface 74 in thelocation of the staple pockets 108 and with further deployment willresult in the bending the staple legs into the desired closedconfiguration capturing tissue within the staple. The closure force ofthe staple 54 of the present invention is advantageously relatively lowbecause the legs 78, 80, 102 in the four-pronged and two-prongedvariations already have curved or slightly bent configurations and aresimply being bent over against the anvil surface 74 as opposed to beingforced to buckle against the anvil surface. Buckling forces of a beamare much greater than bending forces and conventional staples generallyrequire the buckling of staple legs simultaneously. Conventionalstapling devices require high firing forces to apply the staple lines.The staple legs are forced perpendicular to the anvil pockets forcingthem to buckle. These high forces apply significant stresses to thedevice components and can cause fatigue for the user. Therefore, thepresent stapler greatly reduces forces required to deploy and deformstaples. The staple forming forces of the present invention arerelatively low when compared with conventional staple designs providingreduced actuation forces for the user.

As the I-beam 32 is advanced, a blade on the I-beam 32 severs tissuebetween the already-stapled tissue. After the staples are fired, thehandle assembly 12 is switched into the third mode of operation in whichthe I-beam 32 is returned proximally to its starting position. A gearswitch button is depressed which rotates the actuator shaft 90 degreesso that the reverse teeth on the actuator come into contact with areverse driver. The reverse driver is connected to the handle by aseries of gears. When the handle is squeezed, the reverse driver pullsthe actuator and I-beam 32 back. The trigger handle is squeezed multipletimes to return the I-beam 32 to its original position. The I-beam 32 isreturned to its original proximal position to open the jaws. With theI-beam 32 returned and fully retracted, the spring biased upper jaw 48opens allowing the stapled tissue to be released from the jaws. When theactuator and I-beam 32 is returned, the stapler cartridge assembly 14can be detached from the handle assembly 12 and new stapler cartridgeassembly 14 can be attached to continue stapling.

Turning now to FIGS. 64-65, there is shown a cross-sectional view of theend effector 18 taken perpendicular to the longitudinal axis with theI-beam 32 located in the cross-section. In the present invention, astapler is provided that has an end effector 18 with a smaller diameter,such as in the range of 5-10 mm, without significantly changing theability of the smaller stapler of the present invention to staple tissuehaving the same thickness as a relatively larger stapler, that iskeeping the gap width between the upper jaw 48 and the lower jaw 50substantially the same. This is accomplished by employingcircumferential staple channels 53 in the lower jaw 50 with staples 54,100 and pushers 58 configured to function within the circumferentialchannels 53. The circumferential channels 53 take advantage of thelonger distance transcribed by a circumferential distance within theouter perimeter of the substantially circular cross-section of the endeffector 18 relative to a shorter distance transcribed by a linerepresented by line 7 b having a length SB shown in FIG. 1B that isperpendicular to a chord representing the upper surface of the lower jaw48. In order to maximize the length of the circumferential line segmentthat is located within the outer perimeter of the circular cross-sectionand representative of a circumferential staple channel 53, the staplechannel 53 is advantageously located as close to the outer perimeter aspossible. Such placement of the outermost staple channel 53 permits theinner staple line that lies closest to the I-beam 32 to be locatedfurther away from the diametrical blade line and also allows for alonger radially-outermost staple channel 53 for receiving a staple withlonger legs for the secure stapling of thicker tissues. In traditionallinear staples, the lower jaw 50 comprises an outer lower jaw 51 thatforms a semi-cylindrical shell of substantial thickness. Inside thisshell of the outer lower jaw 51, the staples and pushers are resident.One of the functions of the outer lower jaw 51 other than forming acontainer for the staples is to provide structural rigidity and strengthto the lower jaw so that when the staples are deployed the actuationforce does not crack open, deform or bend the lower jaw itself.Therefore, the outer lower jaw 51 is typically made of strong plastic ormetal of a certain thickness. This thickness of the outer lower jaw 51is reduced in the present invention as shown in FIGS. 64-65 so that theoutermost staple channel 53 can be located as close to the perimeter aspossible to maximize the staple leg length that can be located thereinas well as maximize the distance of the innermost staple channel awayfrom the blade line. However, the thinner outer lower jaw 51 sacrificeslower jaw 50 strength and rigidity. This weakening is solved in thepresent invention by forming a frame 112 that is located inside theouter lower jaw 51 in an endoskeleton-like configuration as opposed tothe exoskeleton-like configuration of traditional staplers in which theouter lower jaw 51 is made as thick as possible to provide structuralrigidity to the end effector. The endoskeleton-like frame 112 of thepresent invention may be part of or separate from the inner lower jaw52. The frame 112 has a thickness of approximately 0.025 inches andextends along the length of the lower jaw 50. The frame 112 is made ofstrong plastic or metal and forms the upper surface 114 of the lower jaw50 from which the staple channels 53 open and from which staples exit.The frame 112 forms a substantial T-shape configuration that is divideddown the midline of the “T” by the central lower jaw channel 55 in whichthe I-beam 32 translates. The bottom portion 36 of the I-beam 32 issubstantially equal in width to the width of the vertical portion of the“T” which comprises the width of two frames 112 and the width of thecentral lower jaw channel 55 as can be seen in FIGS. 64-65. The bottomportion 36 of the I-beam 32 is interconnected to the top portion 34 ofthe I-beam 32 by a middle portion 38 of the I-beam 32. The middleportion of the I-beam 32 is substantially the same thickness as thethickness of one frame 112. The T-shaped frame 112 is formed by thejuxtaposition of two L-shape elements spaced apart from each other bythe central lower jaw channel 55. The horizontal portions of theL-shaped elements 116A, 116B or portions that are transverse to theI-beam 32 extend all the way to the perimeter 118. In the variationshown in FIGS. 64-65, the frame 112 has angled horizontal or transverseelements 120 which form a substantially Y-shaped frame 112. Hence, theL-shaped elements 116 form obtuse angles instead of substantially rightangles common to the T-shape. The angled transverse elements 120 extendall the way to the perimeter 118 as shown in FIGS. 64-65. The transverseelements 120 include a point of inflection at which the transverseelements transition from being perpendicular to the middle portion 38 ofthe I-beam 32 to being angled with respect to the middle portion 38.This angulation of the frame 112 opens up more space inside the lowerjaw 50, in particular, adjacent to the perimeter where longer stapleslegs can be accommodated. In this variation, the upper jaw 48 includes areinforcement 122 divided by the central slot 76 in the upper jaw 48.The reinforcement 122 of the upper jaw 48 includes the anvil surface 74.The anvil surface 74 is generally angled in a manner that parallels orcorresponds substantially with the angle of upper surface 114 of thelower jaw 50. The gap for capturing tissue is defined between the anvilsurface 74 and the upper surface 114 of the lower jaw 50. Thereinforcement 122 is made of metal or plastic.

FIG. 65 illustrates the staple channels 53 formed in the configurationof the end effector 18 of FIG. 64 having the endoskeleton-like frame 112configuration. There are shown two staple channels 53 on either side ofthe I-beam 32, an outermost channel 53 a and an innermost channel 53 b.The outermost channel 53 a closely approximates the perimeter 118 and islocated adjacent to the outer lower jaw 51 having a radius of curvaturethat is approximately the same as the radius of curvature of theperimeter 118 of the lower jaw 50. The innermost channel 53 b has aradius of curvature that is larger than the radius of curvature of theoutermost channel 53 a. The upper surface 114 of the lower jaw 50 andthe anvil surface 74 are substantially parallel to each other such thatstaples exiting the channels 53 a, 53 b will be oriented such that thestaple legs are substantially perpendicular to the anvil surface 74. Theangled tansverse elements 120 of the frame 112 are advantageously angledupwardly thereby maximizing the space of the inner lower jaw 52 andlength of the channels 53, in particular the length of the outermostchannel 53 a which accommodates the use of staples with longer legs forstapling tissue across the gap between the anvil surface 74 and uppersurface 114 of the lower jaw 50.

FIG. 66A illustrates another variation of the end effector 18 thatmaximizes the space of the inner lower jaw 52 and length of the staplechannels 53 while providing a configuration for reinforcing the endeffector 18 with a thinner outer lower jaw 51. In the variation of FIG.66A, the reinforcement for keeping the end effector 18 from bending orsplaying apart is found in the configuration of the I-beam 32, inparticular the configuration of the top portion 34 and bottom portion 36of the I-beam 32. Both the top portion 34 and bottom portion 36 of theI-beam 32 have bulbous or enlarged lateral distal ends 124, 126,respectively. The top portion 34 of the I-beam 32 translates inside anupper jaw central slot 76 that is shaped to correspond with the enlargedbulbous distal ends 124. Also, the bottom portion 36 of the I-beam 32translates inside a central lower jaw channel 55 that is shaped tocorrespond with the enlarged bulbous distal ends 126. These enlargedbulbous lateral distal ends 124, 126 strengthen the end effector 18keeping it together when actuation forces are applied. Other variationsof the I-beam 32 are shown in FIGS. 66B-66D. The variations of FIGS.66B-66D illustrate top and bottom portions 34, 36 of the I-beam 32having teeth that extend away from the outer perimeter to provide anincreased thickness and lateral strength improvement. FIG. 66Aillustrates a curved anvil surface 74 that is convex from the viewpointof the gap and a curved upper surface 114 of the lower jaw 50 that isconcave from the viewpoint of the gap. In the variation shown in FIG.66A, the radius of curvature of the upper surface 114 of the lower jaw50 is substantially the same as the radius of curvature of anvil surface74, excluding any anvil pocket formations and curvatures. The curvedupper surface 114 of the lower jaw 50 advantageously provides more spacein the inner lower jaw 52 particularly near the perimeter 118 where dueto the concave curvature of the upper surface 114 more space is providedto receive staples with longer legs. Also, staple legs exiting thechannels 53 at the upper surface 114 are directed substantiallyperpendicularly against the anvil surface 74 due to the substantiallymatching radii of curvature of the upper surface 114 and anvil surface74. In one variation, the radii of curvature of the upper surface 114and anvil surface 74 also substantially equal the radius of curvature ofthe perimeter 118.

Turning now to FIGS. 67-69, another variation of the end effector 218will be described. The end effector 218 includes an upper jaw 248 hingedto a lower jaw 250. When the jaws 248, 250 are in a closed orientation,they form a substantially circular cross-section. The lower jaw 250includes a staple housing or staple cartridge 252 containing a pluralityof staples 254. The lower jaw 250 comprises a hollow semi-cylindricalshell or outer lower jaw (not shown) and a conformingly-shaped innerlower jaw or cartridge 252 disposed inside the outer lower jaw. Theinner lower jaw 252 may or may not be removable and replaceable like acartridge for introducing more staples 254 for continued firing. In avariation in which the inner lower jaw 252 is fixed, the entire stapler10 is disposable after a single firing or, alternatively, the staplercartridge assembly 14 serves as a disposable cartridge and is removedand replaced for continued firing. The inner lower jaw 252 includes aframe 247 defining a plurality of channels 253 or staple pathwaysconfigured to receive staples 254 and serve as a guide for deliveringthe staples 254 towards the upper jaw 248. Each channel 253 forms a topopening at the top surface of the lower jaw 250 through which a staple254 exits the lower jaw 250. The inner lower jaw 252 includes a centralchannel 255 that extends longitudinally and is configured to receive alongitudinally-translating I-beam slider 232. Each channel 253 extendsbetween the top opening and a bottom opening in the top surface of thelower jaw 250. The bottom opening is in communication with a pluralityof ribs forming the frame 247. In the variation shown in FIGS. 67-69,there are two rows of staple channels 253 on either side of the centralchannel 255. The two rows, an inner row and an outer row, of staplechannels 253 on one side of the central channel are configured such thatthey are staggered and not aligned with each other in order to form asealed tissue closure. The two rows, an inner row and an outer row, ofstaple channels 253 on the other side of the central channel 255 arealso staggered as shown. Along the longitudinal axis, the staplechannels 253 comprising the inner row are longitudinally defined by aplurality of inner ribs 239 extending from the top surface. The staplechannels 253 comprising the outer row are longitudinally bound anddefined by a plurality of outer ribs 241 spaced apart along the lengthof the lower jaw 250. The outer ribs 241 are connected to a spine 237 ofthe frame 247 at the bottom of the lower jaw 250. Each channel 253provides a curved pathway or arc from the top opening of the channel forguiding a curved staple 254 placed within it. In a cross-section takenperpendicular to the longitudinal axis of the end effector 218, thechannels 253 define a curved pathway having a radius of curvature thatsubstantially matches the radius of curvature of the outer lower jaw andeach channel 253 forms a circumferential delivery pathway for the staple254. In one variation, the channels 253 are concentric about the centerpoint of a cross-section taken perpendicular to the longitudinal axis ofthe closed jaws 248, 250. A two-pronged staple 254 is shown residing inthe channels 253. An inner pusher 256 is shown disposed inside each ofthe channels 253 of the inner row and an outer pusher 258 is disposedinside each of the channels 253 of the outer row.

With reference to FIGS. 70-71, the inner pusher 256 will now bedescribed. The inner pusher 256 is curved to conform to the curvature ofthe staple channels 253 in which it is disposed. The inner pusher 256 isconfigured to contact the leading surface of the I-beam slider 232 andin turn contact at least one staple 254. The inner pusher 256 isconfigured for interfacing between the I-beam slider 232 and one or morestaples 254. The inner pusher 256 includes a top surface 260 and abottom surface 262 interconnected by an outer surface 264 and an innersurface 266 and two end surfaces 268, 270. The top surface 260 isconfigured to contact one or more staples 254 and as such comprises astaple contacting surface. The top surface 260 of the inner pusher 256includes a channel 261 having a curved surface adapted to cradle andstabilize the base of a staple 254. The outer surface 264 of the innerpusher 256 includes a channel 265 that is configured to receive part ofan outer rib 241 which guides the upward movement of the inner pusher256 along its curved trajectory when moved by the slider 232 preventingit from being displaced longitudinally. Between the inner surface 266and the outer surface 264, the inner pusher 256 is narrower toward thetop surface 260 and wider toward the bottom surface 262. The innerpusher 256 extends longitudinally between two end surfaces 268, 270. Thebottom surface 262 includes an I-beam slider contacting surface 272configured to contact the leading surface 244 of the I-beam slider 232.The I-beam slider contacting surface 272 is shaped to conform to theleading surface 244. If the leading surface 244 of the I-beam slider 232is helical in shape, then the contacting surface 272 is also helical.The slider contacting surface 272 is shown to be angular or bi-angularin the FIGS. 73-76. The inner surface 266 is slightly concave and theouter surface 266 is slightly convex. Both outer and inner surfaces 264,266 are substantially concentric with respect to each other. In onevariation, the outer and inner surfaces 264, 266 are concentric withrespect to the center point of a cross-section taken perpendicular thelongitudinal axis of the jaws 248, 250 with the jaws 248, 250 in aclosed configuration. In one variation, the outer and inner surfaces264, 266 have a curvature that substantially matches the curvature ofthe channel 253 in which it resides. In one variation, the channel 253is circumferential to a cross-section perpendicular to the longitudinalaxis of the jaws 248, 250 with the jaws 248, 250 in a closedconfiguration and the side surfaces 64, 66 of the pusher substantiallymatch the circumferential curvature. The end surfaces 268 and 270 aresubstantially parallel and perpendicular. When urged by the I-beamslider 232, each inner pusher 256 contacts a staple 254 and travelssmoothly within its respective channel 253.

With reference to FIG. 72, the outer pusher 258 will be described. Theouter pusher 258 is curved to conform to the curvature of the staplechannels 253 in which it is disposed. The outer pusher 258 is configuredto contact the leading surface of the I-beam slider 232 and in turncontact at least one staple 254. The outer pusher 258 is configured forinterfacing between the I-beam slider 232 and one or more staples 254.The outer pusher 258 includes a top surface 259 and a bottom surface 263interconnected by an outer surface 275 and an inner surface 277 and twoend surfaces 269, 271. The top surface 259 is configured to contact oneor more staples 254 and as such comprises a staple contacting surface.The top surface 259 of the outer pusher 258 includes a channel 273having a curved surface adapted to cradle and stabilize the base of astaple 254. The inner surface 277 of the outer pusher 258 includes aprojection 257 that is configured to abut between the end surfaces 268,270 of adjacent inner pushers 256 as shown in FIGS. 73, 74 and 75preventing the inner pusher 256 from being displaced longitudinally and,therefore, helping to guide the trajectory of the inner pusher 256.Between the inner surface 277 and the outer surface 275, the outerpusher 258 is narrower toward the top surface 259 and wider toward thebottom surface 263. The outer pusher 256 extends longitudinally betweenthe two end surfaces 269, 271. The bottom surface 263 includes an I-beamslider contacting surface 279 configured to contact the leading surface244 of the I-beam slider 232. The I-beam slider contacting surface 279is shaped to conform to the leading surface 244. If the leading surface244 of the I-beam slider 232 is helical in shape, then the contactingsurface 279 is also helical. The slider contacting surface 279 is shownto be angular or bi-angular in the FIGS. 72-76. The inner surface 277 isslightly concave and the outer surface 275 is slightly convex. Bothouter and inner surfaces 275, 277 are concentric with respect to eachother. In one variation, the outer and inner surfaces 275, 277 areconcentric with respect to the center point of a cross-section takenperpendicular the longitudinal axis of the jaws 248, 250 with the jaws248, 250 in a closed configuration. In one variation, the outer andinner surfaces 275, 277 have a curvature that substantially matches thecurvature of the channel 253 in which it resides. In one variation, thechannel 253 is circumferential to a cross-section perpendicular to thelongitudinal axis of the jaws 248, 250 with the jaws 248, 250 in aclosed configuration and the outer and inner surfaces 275, 277 of theouter pusher 258 substantially match the circumferential curvature. Theend surfaces 269 and 271 are substantially parallel and perpendicular.When urged by the I-beam slider 232, each outer pusher 258 contacts astaple 254 and travels smoothly within its respective channel 253.

With particular reference to FIGS. 73-75, it can be seen that theleading surface 244 of the I-beam slider 232 initially contacts thecontacting surface 272 of the inner pusher 256. The opposite end surface270 will abut the projection 257 of the outer pusher 258. In particular,at least a portion of the thickness, approximately half of the widerlower end of the inner pusher 256, of the end surface 270 will contactthe projection 257 of the outer pusher 258. Also, at least a portion ofthe thickness, approximately half of the wider lower end of the innerpusher 256, of the end surface 270 will contact a distally located innerrib 239. As such, the application of force by the I-beam slider 232 uponthe angled contacting surface 272 will direct the inner pusher 256upwardly toward the top surface and force the staple 254 through theopenings 253. The inner pusher 256 will also travel on the rail-likeouter rib 241 with the outer rib 241 being located within the channel265. Abutment of the inner pusher 256 against the inner rib 239, outerrib 241 and against the projection 257 stabilizes the position of theinner pusher 256 when in contact with the I-beam slider 232 and, whenthe inner pusher 256 is moved, provide a clearance for I-beam slider 232to travel distally and into contact with an outer pusher 258. After theinner pushers 256 on either side of the central channel 255 are movedout of the way, the leading surface 244 of the I-beam slider 232 will inturn contact the contacting surface 279 of adjacent outer pushers 258 oneither side of the central channel 255. Upon contact with the outerpusher 258, at least a portion of the distal end surface 271 will abutthe outer rib 241 and the outer pusher 258 will be directed upwardlywithin the channel 253 moving the staple 254 at the top surface 259 outof the channel 253. Hence, the leading surface 244 of the I-beam slider232 will travel along the longitudinal length of the lower jaw 250pushing a pair of inner pushers 256 followed by a pair of outer pushers258 sequentially and consecutively repeatedly to deploy the staples 254across the gap between upper jaw 248 and lower jaw 250. While only asegment of the end effector 215 illustrating two inner pushers 256 andtwo outer pushers 258 is shown in the figures, the segment is repeatedalong the length of the lower jaw 250.

With continued reference to FIGS. 73-77, the I-beam slider 232 will nowbe described in greater detail. The I-beam slider 232 of FIGS. 73-76 issubstantially similar to the I-beam slider 32 of FIGS. 7-12. The I-beamslider 232 includes a top portion 234 and bottom portion 236interconnected by a middle portion 238. The top portion 234 includes acurved top. The middle portion 238 includes a blade 242, which wouldinclude a sharp leading edge that is shown as a blunt surface in FIGS.73-76. At the back end, the middle portion 238 includes a portion forconnecting with the extended I-beam portion 30 as shown in FIG. 6. Thebottom portion 236 leads the front end of the I-beam slider 232 andincludes a curved bottom with a convex outer surface and a leadingsurface 244 that resembles a snowplow. The leading surface 244 includestwo converging surfaces that meet at a vertical line or tip. Eachconverging surface extends outwardly from the tip in a helical spiralfashion, that is, it not only extends upwardly, but also, spirals orcurves or rotates with respect to the longitudinal axis of the I-beamslider 232 to create the helix wedge design. The front-elevational viewof the I-beam is substantially in the shape of a capital letter “I”having a lower curved portion. The I-beam 232 slides longitudinallyinside the end effector 218 and as such may be called a slider. TheI-beam/slider 232 is configured to urge staples out of the end effector218 via the leading surface 244.

Turning now to FIGS. 78-79, a two-pronged staple 300 according to thepresent invention that is suitable for use with an end effector 218described in FIGS. 67-77 as well as other embodiments found in thisspecification. In FIGS. 78-79, the two-pronged staple 300 is shown inits undeformed or open configuration. The staple 300 includes two legs302 interconnected by a base 304. The base 304 serves as a contactsurface for engagement with the inner or outer pushers 256, 258. Thelegs 302 extend upwardly from the base 304 and curve to one side as canbe clearly seen in FIG. 79. The curvature of the staple legs 302correspond to the curvature of the circumferential channels 253 intowhich they are disposed and along which they travel as they are urged bythe pushers 256, 258 coming sequentially into contact with the I-beamslider 232. The curvature of the staple legs 302, therefore, alsosubstantially corresponds to the circumference of the lower jaw 250. Theend of each leg 302 is angled and forms a sharp tip 306. The tip 306 maybe formed in any manner and may have any geometric shape that issuitable for puncturing and penetrating tissue through which the staple300 is delivered.

Turning now to FIGS. 80-84, there is shown the staple 300 of FIGS. 78-79in a second or deformed configuration after complete actuation of thestapler. Deployment of the two-pronged staple 300, results in the legs302 contacting the anvil surface of the upper jaw 248 and beingdeformed. The legs 302 are deflected toward each other such that thetips 306 are angled vertically downwardly toward the base 304. The legs302 contact the anvil surface wherein anvil pockets that are alignedwith the exit openings in the top surface of the lower jaw 250 may beformed to guide the proper deformation of the staple legs 302. Thedeformed staple 300 has a substantially B-shaped configuration andmaintains a potato chip-like curvature as shown in FIG. 84. The legs 302are deflected substantially in a longitudinal direction along the lengthof the end effector 218.

Turning now to FIGS. 85-89, a two-pronged staple 310 according to thepresent invention that is suitable for use with an end effector 218described in FIGS. 67-77 as well as other embodiments found in thisspecification. In FIGS. 85-89, the two-pronged staple 310 is shown inits undeformed or open configuration. The staple 310 includes two legs312 interconnected by a base 314. The base 314 serves as a contactsurface for engagement with the inner or outer pushers 256, 258. Thelegs 312 extend upwardly from the base 314 and curve to one side as canbe clearly seen in FIG. 89 defining a concave side and a convex side.The curvature of the staple legs 312 correspond to the curvature of thecircumferential channels 253 into which they are disposed and alongwhich they travel as they are urged by the pushers 256, 258 comingsequentially into contact with the I-beam slider 232. The curvature ofthe staple legs 312, therefore, also substantially corresponds to thecircumference of the lower jaw 250. The end of each leg 312 forms asharp tip 316. The tip 316 may be formed in any manner and may have anygeometric shape that is suitable for puncturing and penetrating tissuethrough which the staple 310 is delivered.

Turning now to FIGS. 90-93, there is shown the staple 310 of FIGS. 85-89in a second or deformed configuration after complete actuation of thestapler. Deployment of the two-pronged staple 310, results in the legs312 contacting the anvil surface of the upper jaw 248 and beingdeformed. The legs 312 are deflected toward one direction to close thepre-deformed curvature into a nearly closed circular configuration. Thetips 306 are generally angled vertically downwardly toward the base 314.The legs 312 contact the anvil surface wherein anvil pockets that arealigned with the exit openings in the top surface of the lower jaw 250may be formed to guide the proper deformation of the staple legs 312.Each of the legs 312 of the deformed staple 310 has a substantiallycircular configuration with each circular configuration lying in a planethat is perpendicular to the base 314. The legs 312 of staple embodiment310 are deflected laterally to the longitudinal axis of the end effector218.

Referring back to FIGS. 67-68, the upper jaw 248 of the end effector 218will now be described. The upper jaw 248 is substantiallysemi-cylindrical in shape to conform to a cylindrical lumen of a cannulain which it is inserted. The upper jaw 248 includes a central slot 276that extends longitudinally. The central slot 276 is conformingly shapedand configured to receive the top portion 234 of the I-beam slider 232and at least a portion of the narrower middle portion 238 of the I-beamslider 232 such that the I-beam slider 232 is capable of longitudinalmovement relative to the upper jaw 248 inside and along the central slot276. The central slot 276 includes an open proximal end which is rampedand configured to cam against the beveled front end of the I-beam slider232. The upper jaw 248 is spring biased in an open orientation withrespect to the lower jaw 250 and as the beveled front end of the I-beamslider 232 enters the central slot 276, and in particular, the topportion 234 enters the wider upper end of the central slot 276, theupper and lower jaws 248, 250 are forced to close. Back and forthmovement of the I-beam slider 232, into and out of the central slot 276or against the proximal opening of the central slot 276, opens andcloses the end effector 218 allowing the user to grasp and releasetissue and reposition the stapler 10. With the end effector 218 in theclosed configuration, the I-beam slider 232 is capable of furtherlongitudinal translation within the central slot 276. Following theejection of staples 254, the I-beam slider 232 is retracted proximallyvia the handle assembly 12 and as the I-beam slider 232 exits thecentral slot 276 the spring biased upper jaw 248 moves into an openorientation. Following the ejection of staples 254 and retraction of theI-beam slider 232, repeated forward translation of the I-beam slider 232inside the central slot 276 is prevented by a lock-out mechanism toavoid inadvertent use of an already-fired cartridge.

Also with reference to FIGS. 67-68, the upper jaw 248 further includesan inner anvil surface 274 or plate that faces and is spaced apart fromthe lower jaw 250 when in the closed position. The anvil surface 274 isconfigured to receive the legs of a staple 254 and guide, deflect,angulate, bend, crimp or clinch the staple legs as the staple 254 isurged through tissue against the anvil surface 274. To facilitate theformation of staples 254 to secure tissue, a plurality of staple-formingpockets is shown in FIGS. 67-68 are included in the anvil surface 274.These surface formations of a typical anvil aid in the deformation ofthe staple as it is deployed to achieve proper staple closure. Thestaple-forming pockets are aligned with the exit openings of channels253 in the lower jaw 250. The staple-forming pockets generally includetwo adjacent staple leg forming cups having a curved or slopedchanneling surface formed around the perimeter of each of the stapleforming cups. The two adjacent staple leg forming cups form a dog boneshape that facilitates the formation of consistent B-shaped staples fromgenerally square-cornered U-shaped undeformed staples. To laterally urgethe legs of a staple relative to the base of the staple as in thevariation of the staple shown in FIGS. 85-93, an anvil surface or staplepocket is configured accordingly. Separate staple-forming pockets areprovided at each staple forming location opposite the cartridge channels253 of the lower jaw 250.

As described earlier, the leg length of a staple employed in aconventional surgical stapler is generally limited by a distanceperpendicular to the upper surface 402 of the lower jaw 404 which isdepicted by a line segment 400 that is representative of the length of astaple leg in FIG. 94. One end 401 of the line segment 400 is proximalto the upper surface 402 of the lower jaw 404 and the other end 403 ofthe line segment 400 is proximal to the lower periphery of the lower jaw404. The lower jaw 404 is depicted by a partial circle having anapproximate diameter of 0.5 inches. The distance from the upper surface402 of the lower jaw 404 to the distal most point on the circle 404 atthe diameter of the lower jaw 404 is approximately 0.38. Therefore, asdepicted in FIG. 94, the length of the line segment or otherwise, thelength of a staple leg 400 is approximately 0.34 inches for a staplehaving a leg wire diameter of approximately 0.01 inches in aconventional linear stapler design. In contrast to a linear stapler ofFIG. 94, a schematic of a circumferential stapler lower jaw 414 of thepresent invention is depicted in FIG. 95 wherein the length of a stapleleg is defined by a curve 400 instead of a straight line inside thelower jaw 414. One end 411 of the staple leg 410 is near the uppersurface 412 of the lower jaw 414 and the other end 413 is near the lowerperiphery of the lower jaw 414. The end 413 is in the same location asthe end 403 of FIG. 94. The staple leg 410 of FIG. 95 is curveddepicting a staple 410 residing inside a curved channel of acircumferential stapler according to the present invention. Given thesame dimensions for the lower jaw diameter (approximately 0.5 inches)and the same distance from the upper surface 412 to the diametricaloutermost point on the circle 414 of approximately 0.38 inches, thestaple leg 410 is approximately 0.41 in length compared to a staple leg400 having a length of only approximately 0.34. Therefore, the stapleleg length is approximately 20% longer in the present invention. Hence,the advantages of the present invention are demonstrably longer staplelengths which provide the ability to staple through and hold thickertissue segments in a stapler of the same diameter.

Turning now to FIG. 96, there is shown yet another schematic of acircumferential stapler design according to the present invention. FIG.96 depicts a staple leg length 420 as a curve inside a schematic of astapler lower jaw 424. The staple leg 420 has one end 421 near the uppersurface 422 of the lower jaw 424 and a second end 423 also near theupper surface 422 of the lower jaw 424 for a total staple leg length ofapproximately 0.97 inches which is significantly longer than the staplelength of FIGS. 94 and 95. The lower jaw 424 is depicted as a partialcircle having a diameter of approximately 0.5 inches and having adistance from the upper surface 422 to a diametrical outermost point onthe circle of approximately 0.38 inches which are the same dimensionsfor the lower jaw 424 as depicted in FIGS. 94 and 95. In this variation,the circumferential design takes advantage of firing along nearly theentire circumference of the lower jaw 424 in contrast to a perpendiculardistance on either side of the midline as shown in FIG. 94 or along apart of the circumference as shown in FIG. 95. The staple length of FIG.96 is approximately 285% longer than the conventional stapler depictedin FIG. 94 which illustrates the tremendous advantage in terms of alonger staple leg length afforded by designs comprising circumferentialfiring according to the present invention.

Conventional laparoscopic staplers are currently approximately 12millimeters in diameter which require a larger sized cannula forinsertion and, hence, a larger incision in the patient. The laparoscopicstapler 10 of the present invention with rotational firing has adiameter of approximately 0.200-0.400 inches which will advantageouslyfit inside smaller diameter cannulas that require smaller incisions inthe patient while at the same time have capabilities of stapling thesame thickness tissue as the larger staplers. The circumferentialstapler offers at least a 20% reduction in size of the outer diameter ofthe stapler while delivering staples with the same leg length as in alarger diameter stapler having a conventional design. The smallerincision results in less pain, less bleeding, faster patient recoverytimes and a smaller scar visible after the operation. The stapler of thepresent invention is particularly well-suited for laparoscopicprocedures; however, the invention is not so limited and the stapler ofthe present invention can be used in open surgical procedures equallyeffectively.

It is understood that various modifications may be made to theembodiments of the surgical stapler disclosed herein. Therefore, theabove description should not be construed as limiting, but merely asexemplifications of preferred embodiments. Those skilled in the art willenvision other modifications within the scope and spirit of the presentdisclosure.

We claim:
 1. A surgical stapler comprising: a handle assembly connectedto a stapler cartridge assembly; the stapler cartridge assembly havingan end effector at the distal end; the end effector comprising an upperjaw connected to a lower jaw such that the upper jaw is movable via thehandle assembly relative to the lower jaw between an open configurationand a closed configuration; the lower jaw has an upper surface and theupper jaw has an anvil surface; wherein in the closed configuration, agap is defined between the upper surface and anvil surface for receivingtissue to be stapled; the lower jaw further includes a plurality ofstaple channels arranged longitudinally along the length of the lowerjaw and configured to receive staples; wherein actuation of the staplerat the handle assembly moves staples from an undeformed configurationinside the channel against the anvil surface into a deformedconfiguration in the gap to staple tissue located in the gap; eachstaple channel having an opening at the upper surface; wherein a centerpoint and midline are defined in a cross-section taken perpendicular tothe longitudinal axis of the end effector with the jaws in a closedconfiguration; wherein one or more staple line is defined on either sideof the midline by a plurality of channel openings aligned along thelongitudinal length of the upper surface; wherein one or more staplechannels are curved; the surgical stapler of further including aplurality of staples disposed inside the staple channels; each staplehaving a base with extending legs; each staple having an undeformedconfiguration in which the staple legs are curved to conform to thecurvature of the staple channels in which they reside and a deformedconfiguration in which the staple legs are closed to capture tissue. 2.The surgical stapler of claim 1 wherein each staple has two legs.
 3. Thesurgical stapler of claim 1 wherein each staple has four legs.
 4. Asurgical stapler comprising: a handle assembly connected to a staplercartridge assembly; the stapler cartridge assembly having an endeffector at the distal end; the end effector comprising an upper jawconnected to a lower jaw such that the upper jaw is movable via thehandle assembly relative to the lower jaw between an open configurationand a closed configuration; the lower jaw has an upper surface and theupper jaw has an anvil surface; wherein in the closed configuration, agap is defined between the upper surface and anvil surface for receivingtissue to be stapled; the lower jaw further includes a plurality ofstaple channels arranged longitudinally along the length of the lowerjaw and configured to receive staples; wherein actuation of the staplerat the handle assembly moves staples from an undeformed configurationinside the channel against the anvil surface into a deformedconfiguration in the gap to staple tissue located in the gap; eachstaple channel having an opening at the upper surface; wherein a centerpoint and midline are defined in a cross-section taken perpendicular tothe longitudinal axis of the end effector with the jaws in a closedconfiguration; wherein one or more staple line is defined on either sideof the midline by a plurality of channel openings aligned along thelongitudinal length of the upper surface; wherein one or more staplechannels are curved; and wherein each staple has two legs and thestapler is configured such that upon actuation one leg contacts theanvil surface before the other leg.
 5. A surgical stapler comprising: ahandle assembly connected to a stapler cartridge assembly; the staplercartridge assembly having an end effector at the distal end; the endeffector comprising an upper jaw connected to a lower jaw such that theupper jaw is movable via the handle assembly relative to the lower jawbetween an open configuration and a closed configuration; the lower jawhas an upper surface and the upper jaw has an anvil surface; wherein inthe closed configuration, a gap is defined between the upper surface andanvil surface for receiving tissue to be stapled; the lower jaw furtherincludes a plurality of staple channels arranged longitudinally alongthe length of the lower jaw and configured to receive staples; whereinactuation of the stapler at the handle assembly moves staples from anundeformed configuration inside the channel against the anvil surfaceinto a deformed configuration in the gap to staple tissue located in thegap; each staple channel having an opening at the upper surface; whereina center point and midline are defined in a cross-section takenperpendicular to the longitudinal axis of the end effector with the jawsin a closed configuration; wherein one or more staple line is defined oneither side of the midline by a plurality of channel openings alignedalong the longitudinal length of the upper surface; wherein one or morestaple channels are curved; and wherein each staple has four staple legsand the stapler is configured such that upon actuation two legs contactthe anvil surface before the remaining two legs.
 6. A surgical staplercomprising: a handle assembly connected to a stapler cartridge assembly;the stapler cartridge assembly having an end effector at the distal end;the end effector comprising an upper jaw connected to a lower jaw suchthat the upper jaw is movable via the handle assembly relative to thelower jaw between an open configuration and a closed configuration; thelower jaw has an upper surface and the upper jaw has an anvil surface;wherein in the closed configuration, a gap is defined between the uppersurface and anvil surface for receiving tissue to be stapled; the lowerjaw further includes a plurality of staple channels arrangedlongitudinally along the length of the lower jaw and configured toreceive staples; wherein actuation of the stapler at the handle assemblymoves staples from an undeformed configuration inside the channelagainst the anvil surface into a deformed configuration in the gap tostaple tissue located in the gap; each staple channel having an openingat the upper surface; wherein a center point and midline are defined ina cross-section taken perpendicular to the longitudinal axis of the endeffector with the jaws in a closed configuration; wherein one or morestaple line is defined on either side of the midline by a plurality ofchannel openings aligned along the longitudinal length of the uppersurface; wherein one or more staple channels are curved; wherein thestaple includes two or four legs and all of the legs are bent to thesame side in the deformed configuration.
 7. A surgical staplercomprising: a handle assembly connected to a stapler cartridge assembly;the stapler cartridge assembly having an end effector at the distal end;the end effector comprising an upper jaw connected to a lower jaw suchthat the upper jaw is movable via the handle assembly relative to thelower jaw between an open configuration and a closed configuration; thelower jaw has an upper surface and the upper jaw has an anvil surface;wherein in the closed configuration, a gap is defined between the uppersurface and anvil surface for receiving tissue to be stapled; the lowerjaw further includes a plurality of staple channels arrangedlongitudinally along the length of the lower jaw and configured toreceive staples; wherein actuation of the stapler at the handle assemblymoves staples from an undeformed configuration inside the channelagainst the anvil surface into a deformed configuration in the gap tostaple tissue located in the gap; each staple channel having an openingat the upper surface; wherein a center point and midline are defined ina cross-section taken perpendicular to the longitudinal axis of the endeffector with the jaws in a closed configuration; wherein one or morestaple line is defined on either side of the midline by a plurality ofchannel openings aligned along the longitudinal length of the uppersurface; wherein one or more staple channels are curved; wherein thestaple includes two or four legs and the staple base is aligned parallelto the longitudinal axis and the staple legs are aligned substantiallyperpendicular to the longitudinal axis in the deformed configuration. 8.A surgical stapler comprising: a handle assembly connected to a staplercartridge assembly; the stapler cartridge assembly having an endeffector at the distal end; the end effector comprising an upper jawconnected to a lower jaw such that the upper jaw is movable via thehandle assembly relative to the lower jaw between an open configurationand a closed configuration; the lower jaw has an upper surface and theupper jaw has an anvil surface; wherein in the closed configuration, agap is defined between the upper surface and anvil surface for receivingtissue to be stapled; the lower jaw further includes a plurality ofstaple channels arranged longitudinally along the length of the lowerjaw and configured to receive staples; wherein actuation of the staplerat the handle assembly moves staples from an undeformed configurationinside the channel against the anvil surface into a deformedconfiguration in the gap to staple tissue located in the gap; eachstaple channel having an opening at the upper surface; wherein a centerpoint and midline are defined in a cross-section taken perpendicular tothe longitudinal axis of the end effector with the jaws in a closedconfiguration; wherein one or more staple line is defined on either sideof the midline by a plurality of channel openings aligned along thelongitudinal length of the upper surface; wherein one or more staplechannels are curved; and wherein the staple includes two legs connectedto a base and the staple legs and base are aligned parallel to thelongitudinal axis in the deformed configuration in the gap.
 9. Asurgical stapler comprising: a handle assembly connected to a staplercartridge assembly; the stapler cartridge assembly having an endeffector at the distal end; the end effector comprising an upper jawconnected to a lower jaw such that the upper jaw is movable via thehandle assembly relative to the lower jaw between an open configurationand a closed configuration; the lower jaw has an upper surface and theupper jaw has an anvil surface; wherein in the closed configuration, agap is defined between the upper surface and anvil surface for receivingtissue to be stapled; the lower jaw further includes a plurality ofstaple channels arranged longitudinally along the length of the lowerjaw and configured to receive staples; wherein actuation of the staplerat the handle assembly moves staples from an undeformed configurationinside the channel against the anvil surface into a deformedconfiguration in the gap to staple tissue located in the gap; eachstaple channel having an opening at the upper surface; wherein a centerpoint and midline are defined in a cross-section taken perpendicular tothe longitudinal axis of the end effector with the jaws in a closedconfiguration; wherein one or more staple line is defined on either sideof the midline by a plurality of channel openings aligned along thelongitudinal length of the upper surface; wherein one or more staplechannels are curved; the surgical stapler further including a pluralityof staples disposed inside the staple channels; each staple having twolegs spaced apart and connected to a base of the staple; each staplehaving an undeformed configuration inside the channel and deformedconfiguration inside the gap; whereupon actuation, the staple legs aredeflected in a direction transverse to the longitudinal axis of the endeffector into the deformed configuration.
 10. A surgical staplercomprising: a handle assembly connected to a stapler cartridge assembly;the stapler cartridge assembly having an end effector at the distal end;the end effector comprising an upper jaw connected to a lower jaw suchthat the upper jaw is movable via the handle assembly relative to thelower jaw between an open configuration and a closed configuration; thelower jaw has an upper surface and the upper jaw has an anvil surface;wherein in the closed configuration, a gap is defined between the uppersurface and anvil surface for receiving tissue to be stapled; the lowerjaw further includes a plurality of staple channels arrangedlongitudinally along the length of the lower jaw and configured toreceive staples; wherein actuation of the stapler at the handle assemblymoves staples from an undeformed configuration inside the channelagainst the anvil surface into a deformed configuration in the gap tostaple tissue located in the gap; each staple channel having an openingat the upper surface; wherein a center point and midline are defined ina cross-section taken perpendicular to the longitudinal axis of the endeffector with the jaws in a closed configuration; wherein one or morestaple line is defined on either side of the midline by a plurality ofchannel openings aligned along the longitudinal length of the uppersurface; wherein one or more staple channels are curved; and wherein thestaple channels are curved about the center point.
 11. The surgicalstapler of claim 10 wherein the staple includes two legs and the stapleforms a substantial B-shaped deformed configuration.
 12. The surgicalstapler of claim 10 wherein the staple includes two legs and the staplelegs form two open circles in the deformed configuration.
 13. Thesurgical stapler of claim 10 wherein the staple includes two legs andthe staple legs form two open circles residing in two planes that areparallel to each other and also perpendicular to the base of the staplein the deformed configuration.
 14. The surgical stapler of claim 10wherein when in a closed configuration the jaws form a substantiallycircular cross-section taken along the longitudinal axis of the endeffector.
 15. A surgical stapler comprising: a handle assembly connectedto a stapler cartridge assembly; the stapler cartridge assembly havingan end effector at the distal end; the end effector comprising an upperjaw connected to a lower jaw such that the upper jaw is movable via thehandle assembly relative to the lower jaw between an open configurationand a closed configuration; the lower jaw has an upper surface and theupper jaw has an anvil surface; wherein in the closed configuration, agap is defined between the upper surface and anvil surface for receivingtissue to be stapled; the lower jaw further includes a plurality ofstaple channels arranged longitudinally along the length of the lowerjaw and configured to receive staples; wherein actuation of the staplerat the handle assembly moves staples from an undeformed configurationinside the channel against the anvil surface into a deformedconfiguration in the gap to staple tissue located in the gap; eachstaple channel having an opening at the upper surface; wherein a centerpoint and midline are defined in a cross-section taken perpendicular tothe longitudinal axis of the end effector with the jaws in a closedconfiguration; wherein one or more staple line is defined on either sideof the midline by a plurality of channel openings aligned along thelongitudinal length of the upper surface; wherein one or more staplechannels are curved; the surgical stapler further including a pluralityof staples disposed inside the staple channels; each staple having twolegs spaced apart and connected to a base of the staple; each staplehaving an undeformed configuration inside the channel and deformedconfiguration inside the gap; whereupon actuation, the staple legs aredeflected in a direction along the longitudinal axis of the end effectorinto the deformed configuration.
 16. A surgical stapler comprising: ahandle assembly connected to a stapler cartridge assembly; the staplercartridge assembly having an end effector at the distal end; the endeffector comprising an upper jaw connected to a lower jaw such that theupper jaw is movable via the handle assembly relative to the lower jawbetween an open configuration and a closed configuration; the lower jawhas an upper surface and the upper jaw has an anvil surface; wherein inthe closed configuration, a gap is defined between the upper surface andanvil surface for receiving tissue to be stapled; the lower jaw furtherincludes a plurality of staple channels arranged longitudinally alongthe length of the lower jaw and configured to receive staples; whereinactuation of the stapler at the handle assembly moves staples from anundeformed configuration inside the channel against the anvil surfaceinto a deformed configuration in the gap to staple tissue located in thegap; each staple channel having an opening at the upper surface; whereina center point and midline are defined in a cross-section takenperpendicular to the longitudinal axis of the end effector with the jawsin a closed configuration; wherein one or more staple line is defined oneither side of the midline by a plurality of channel openings alignedalong the longitudinal length of the upper surface; wherein one or morestaple channels are curved; the surgical stapler further including aplurality of pushers disposed inside the staple channels that areconfigured to contact and eject staples upon actuation; wherein eachpusher has parallel side surfaces that conform to the curvature of thestaple channel in which it resides.
 17. The surgical stapler of claim 16further including a central channel formed in the upper jaw and thelower jaw along the midline and along the length of the end effector;the central channel being configured to receive a slider longitudinallymovable inside the central channel and configured to sequentiallycontact the plurality of pushers disposed inside the staple channels.